diff --git a/docs/docs/05_flask_smorest/02_data_model_improvements/end/.flaskenv b/docs/docs/05_flask_smorest/02_data_model_improvements/end/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/05_flask_smorest/02_data_model_improvements/end/.flaskenv
+++ b/docs/docs/05_flask_smorest/02_data_model_improvements/end/.flaskenv
@@ -1,2 +1,2 @@
 FLASK_APP=app
-FLASK_ENV=development
\ No newline at end of file
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\ No newline at end of file
diff --git a/docs/docs/05_flask_smorest/03_improvements_on_first_rest_api/end/.flaskenv b/docs/docs/05_flask_smorest/03_improvements_on_first_rest_api/end/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/05_flask_smorest/03_improvements_on_first_rest_api/end/.flaskenv
+++ b/docs/docs/05_flask_smorest/03_improvements_on_first_rest_api/end/.flaskenv
@@ -1,2 +1,2 @@
 FLASK_APP=app
-FLASK_ENV=development
\ No newline at end of file
+FLASK_DEBUG=True
\ No newline at end of file
diff --git a/docs/docs/05_flask_smorest/03_improvements_on_first_rest_api/start/.flaskenv b/docs/docs/05_flask_smorest/03_improvements_on_first_rest_api/start/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/05_flask_smorest/03_improvements_on_first_rest_api/start/.flaskenv
+++ b/docs/docs/05_flask_smorest/03_improvements_on_first_rest_api/start/.flaskenv
@@ -1,2 +1,2 @@
 FLASK_APP=app
-FLASK_ENV=development
\ No newline at end of file
+FLASK_DEBUG=True
\ No newline at end of file
diff --git a/docs/docs/05_flask_smorest/04_new_endpoints_for_api/end/.flaskenv b/docs/docs/05_flask_smorest/04_new_endpoints_for_api/end/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/05_flask_smorest/04_new_endpoints_for_api/end/.flaskenv
+++ b/docs/docs/05_flask_smorest/04_new_endpoints_for_api/end/.flaskenv
@@ -1,2 +1,2 @@
 FLASK_APP=app
-FLASK_ENV=development
\ No newline at end of file
+FLASK_DEBUG=True
\ No newline at end of file
diff --git a/docs/docs/05_flask_smorest/04_new_endpoints_for_api/start/.flaskenv b/docs/docs/05_flask_smorest/04_new_endpoints_for_api/start/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/05_flask_smorest/04_new_endpoints_for_api/start/.flaskenv
+++ b/docs/docs/05_flask_smorest/04_new_endpoints_for_api/start/.flaskenv
@@ -1,2 +1,2 @@
 FLASK_APP=app
-FLASK_ENV=development
\ No newline at end of file
+FLASK_DEBUG=True
\ No newline at end of file
diff --git a/docs/docs/05_flask_smorest/05_reload_api_docker_container/end/.flaskenv b/docs/docs/05_flask_smorest/05_reload_api_docker_container/end/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/05_flask_smorest/05_reload_api_docker_container/end/.flaskenv
+++ b/docs/docs/05_flask_smorest/05_reload_api_docker_container/end/.flaskenv
@@ -1,2 +1,2 @@
 FLASK_APP=app
-FLASK_ENV=development
\ No newline at end of file
+FLASK_DEBUG=True
\ No newline at end of file
diff --git a/docs/docs/05_flask_smorest/05_reload_api_docker_container/start/.flaskenv b/docs/docs/05_flask_smorest/05_reload_api_docker_container/start/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/05_flask_smorest/05_reload_api_docker_container/start/.flaskenv
+++ b/docs/docs/05_flask_smorest/05_reload_api_docker_container/start/.flaskenv
@@ -1,2 +1,2 @@
 FLASK_APP=app
-FLASK_ENV=development
\ No newline at end of file
+FLASK_DEBUG=True
\ No newline at end of file
diff --git a/docs/docs/05_flask_smorest/06_api_with_method_views/end/.flaskenv b/docs/docs/05_flask_smorest/06_api_with_method_views/end/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/05_flask_smorest/06_api_with_method_views/end/.flaskenv
+++ b/docs/docs/05_flask_smorest/06_api_with_method_views/end/.flaskenv
@@ -1,2 +1,2 @@
 FLASK_APP=app
-FLASK_ENV=development
\ No newline at end of file
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\ No newline at end of file
diff --git a/docs/docs/05_flask_smorest/06_api_with_method_views/start/.flaskenv b/docs/docs/05_flask_smorest/06_api_with_method_views/start/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/05_flask_smorest/06_api_with_method_views/start/.flaskenv
+++ b/docs/docs/05_flask_smorest/06_api_with_method_views/start/.flaskenv
@@ -1,2 +1,2 @@
 FLASK_APP=app
-FLASK_ENV=development
\ No newline at end of file
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\ No newline at end of file
diff --git a/docs/docs/05_flask_smorest/07_marshmallow_schemas/end/.flaskenv b/docs/docs/05_flask_smorest/07_marshmallow_schemas/end/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/05_flask_smorest/07_marshmallow_schemas/end/.flaskenv
+++ b/docs/docs/05_flask_smorest/07_marshmallow_schemas/end/.flaskenv
@@ -1,2 +1,2 @@
 FLASK_APP=app
-FLASK_ENV=development
\ No newline at end of file
+FLASK_DEBUG=True
\ No newline at end of file
diff --git a/docs/docs/05_flask_smorest/07_marshmallow_schemas/start/.flaskenv b/docs/docs/05_flask_smorest/07_marshmallow_schemas/start/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/05_flask_smorest/07_marshmallow_schemas/start/.flaskenv
+++ b/docs/docs/05_flask_smorest/07_marshmallow_schemas/start/.flaskenv
@@ -1,2 +1,2 @@
 FLASK_APP=app
-FLASK_ENV=development
\ No newline at end of file
+FLASK_DEBUG=True
\ No newline at end of file
diff --git a/docs/docs/05_flask_smorest/08_validation_with_marshmallow/end/.flaskenv b/docs/docs/05_flask_smorest/08_validation_with_marshmallow/end/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/05_flask_smorest/08_validation_with_marshmallow/end/.flaskenv
+++ b/docs/docs/05_flask_smorest/08_validation_with_marshmallow/end/.flaskenv
@@ -1,2 +1,2 @@
 FLASK_APP=app
-FLASK_ENV=development
\ No newline at end of file
+FLASK_DEBUG=True
\ No newline at end of file
diff --git a/docs/docs/05_flask_smorest/08_validation_with_marshmallow/start/.flaskenv b/docs/docs/05_flask_smorest/08_validation_with_marshmallow/start/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/05_flask_smorest/08_validation_with_marshmallow/start/.flaskenv
+++ b/docs/docs/05_flask_smorest/08_validation_with_marshmallow/start/.flaskenv
@@ -1,2 +1,2 @@
 FLASK_APP=app
-FLASK_ENV=development
\ No newline at end of file
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\ No newline at end of file
diff --git a/docs/docs/05_flask_smorest/09_decorating_responses/end/.flaskenv b/docs/docs/05_flask_smorest/09_decorating_responses/end/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/05_flask_smorest/09_decorating_responses/end/.flaskenv
+++ b/docs/docs/05_flask_smorest/09_decorating_responses/end/.flaskenv
@@ -1,2 +1,2 @@
 FLASK_APP=app
-FLASK_ENV=development
\ No newline at end of file
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\ No newline at end of file
diff --git a/docs/docs/05_flask_smorest/09_decorating_responses/start/.flaskenv b/docs/docs/05_flask_smorest/09_decorating_responses/start/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/05_flask_smorest/09_decorating_responses/start/.flaskenv
+++ b/docs/docs/05_flask_smorest/09_decorating_responses/start/.flaskenv
@@ -1,2 +1,2 @@
 FLASK_APP=app
-FLASK_ENV=development
\ No newline at end of file
+FLASK_DEBUG=True
\ No newline at end of file
diff --git a/docs/docs/06_sql_storage_sqlalchemy/02_create_simple_sqlalchemy_model/end/.flaskenv b/docs/docs/06_sql_storage_sqlalchemy/02_create_simple_sqlalchemy_model/end/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/06_sql_storage_sqlalchemy/02_create_simple_sqlalchemy_model/end/.flaskenv
+++ b/docs/docs/06_sql_storage_sqlalchemy/02_create_simple_sqlalchemy_model/end/.flaskenv
@@ -1,2 +1,2 @@
 FLASK_APP=app
-FLASK_ENV=development
\ No newline at end of file
+FLASK_DEBUG=True
\ No newline at end of file
diff --git a/docs/docs/06_sql_storage_sqlalchemy/02_create_simple_sqlalchemy_model/start/.flaskenv b/docs/docs/06_sql_storage_sqlalchemy/02_create_simple_sqlalchemy_model/start/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/06_sql_storage_sqlalchemy/02_create_simple_sqlalchemy_model/start/.flaskenv
+++ b/docs/docs/06_sql_storage_sqlalchemy/02_create_simple_sqlalchemy_model/start/.flaskenv
@@ -1,2 +1,2 @@
 FLASK_APP=app
-FLASK_ENV=development
\ No newline at end of file
+FLASK_DEBUG=True
\ No newline at end of file
diff --git a/docs/docs/06_sql_storage_sqlalchemy/03_one_to_many_relationships_sqlalchemy/end/.flaskenv b/docs/docs/06_sql_storage_sqlalchemy/03_one_to_many_relationships_sqlalchemy/end/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/06_sql_storage_sqlalchemy/03_one_to_many_relationships_sqlalchemy/end/.flaskenv
+++ b/docs/docs/06_sql_storage_sqlalchemy/03_one_to_many_relationships_sqlalchemy/end/.flaskenv
@@ -1,2 +1,2 @@
 FLASK_APP=app
-FLASK_ENV=development
\ No newline at end of file
+FLASK_DEBUG=True
\ No newline at end of file
diff --git a/docs/docs/06_sql_storage_sqlalchemy/03_one_to_many_relationships_sqlalchemy/start/.flaskenv b/docs/docs/06_sql_storage_sqlalchemy/03_one_to_many_relationships_sqlalchemy/start/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/06_sql_storage_sqlalchemy/03_one_to_many_relationships_sqlalchemy/start/.flaskenv
+++ b/docs/docs/06_sql_storage_sqlalchemy/03_one_to_many_relationships_sqlalchemy/start/.flaskenv
@@ -1,2 +1,2 @@
 FLASK_APP=app
-FLASK_ENV=development
\ No newline at end of file
+FLASK_DEBUG=True
\ No newline at end of file
diff --git a/docs/docs/06_sql_storage_sqlalchemy/04_configure_flask_sqlalchemy/end/.flaskenv b/docs/docs/06_sql_storage_sqlalchemy/04_configure_flask_sqlalchemy/end/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/06_sql_storage_sqlalchemy/04_configure_flask_sqlalchemy/end/.flaskenv
+++ b/docs/docs/06_sql_storage_sqlalchemy/04_configure_flask_sqlalchemy/end/.flaskenv
@@ -1,2 +1,2 @@
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-FLASK_ENV=development
\ No newline at end of file
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\ No newline at end of file
diff --git a/docs/docs/06_sql_storage_sqlalchemy/04_configure_flask_sqlalchemy/start/.flaskenv b/docs/docs/06_sql_storage_sqlalchemy/04_configure_flask_sqlalchemy/start/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/06_sql_storage_sqlalchemy/04_configure_flask_sqlalchemy/start/.flaskenv
+++ b/docs/docs/06_sql_storage_sqlalchemy/04_configure_flask_sqlalchemy/start/.flaskenv
@@ -1,2 +1,2 @@
 FLASK_APP=app
-FLASK_ENV=development
\ No newline at end of file
+FLASK_DEBUG=True
\ No newline at end of file
diff --git a/docs/docs/06_sql_storage_sqlalchemy/05_insert_models_sqlalchemy/end/.flaskenv b/docs/docs/06_sql_storage_sqlalchemy/05_insert_models_sqlalchemy/end/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/06_sql_storage_sqlalchemy/05_insert_models_sqlalchemy/end/.flaskenv
+++ b/docs/docs/06_sql_storage_sqlalchemy/05_insert_models_sqlalchemy/end/.flaskenv
@@ -1,2 +1,2 @@
 FLASK_APP=app
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\ No newline at end of file
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\ No newline at end of file
diff --git a/docs/docs/06_sql_storage_sqlalchemy/05_insert_models_sqlalchemy/start/.flaskenv b/docs/docs/06_sql_storage_sqlalchemy/05_insert_models_sqlalchemy/start/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/06_sql_storage_sqlalchemy/05_insert_models_sqlalchemy/start/.flaskenv
+++ b/docs/docs/06_sql_storage_sqlalchemy/05_insert_models_sqlalchemy/start/.flaskenv
@@ -1,2 +1,2 @@
 FLASK_APP=app
-FLASK_ENV=development
\ No newline at end of file
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\ No newline at end of file
diff --git a/docs/docs/06_sql_storage_sqlalchemy/06_get_models_or_404/end/.flaskenv b/docs/docs/06_sql_storage_sqlalchemy/06_get_models_or_404/end/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/06_sql_storage_sqlalchemy/06_get_models_or_404/end/.flaskenv
+++ b/docs/docs/06_sql_storage_sqlalchemy/06_get_models_or_404/end/.flaskenv
@@ -1,2 +1,2 @@
 FLASK_APP=app
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\ No newline at end of file
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\ No newline at end of file
diff --git a/docs/docs/06_sql_storage_sqlalchemy/06_get_models_or_404/start/.flaskenv b/docs/docs/06_sql_storage_sqlalchemy/06_get_models_or_404/start/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/06_sql_storage_sqlalchemy/06_get_models_or_404/start/.flaskenv
+++ b/docs/docs/06_sql_storage_sqlalchemy/06_get_models_or_404/start/.flaskenv
@@ -1,2 +1,2 @@
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-FLASK_ENV=development
\ No newline at end of file
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\ No newline at end of file
diff --git a/docs/docs/06_sql_storage_sqlalchemy/07_updating_models_sqlalchemy/end/.flaskenv b/docs/docs/06_sql_storage_sqlalchemy/07_updating_models_sqlalchemy/end/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/06_sql_storage_sqlalchemy/07_updating_models_sqlalchemy/end/.flaskenv
+++ b/docs/docs/06_sql_storage_sqlalchemy/07_updating_models_sqlalchemy/end/.flaskenv
@@ -1,2 +1,2 @@
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\ No newline at end of file
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\ No newline at end of file
diff --git a/docs/docs/06_sql_storage_sqlalchemy/07_updating_models_sqlalchemy/start/.flaskenv b/docs/docs/06_sql_storage_sqlalchemy/07_updating_models_sqlalchemy/start/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/06_sql_storage_sqlalchemy/07_updating_models_sqlalchemy/start/.flaskenv
+++ b/docs/docs/06_sql_storage_sqlalchemy/07_updating_models_sqlalchemy/start/.flaskenv
@@ -1,2 +1,2 @@
 FLASK_APP=app
-FLASK_ENV=development
\ No newline at end of file
+FLASK_DEBUG=True
\ No newline at end of file
diff --git a/docs/docs/06_sql_storage_sqlalchemy/08_retrieve_list_all_models/end/.flaskenv b/docs/docs/06_sql_storage_sqlalchemy/08_retrieve_list_all_models/end/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/06_sql_storage_sqlalchemy/08_retrieve_list_all_models/end/.flaskenv
+++ b/docs/docs/06_sql_storage_sqlalchemy/08_retrieve_list_all_models/end/.flaskenv
@@ -1,2 +1,2 @@
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\ No newline at end of file
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\ No newline at end of file
diff --git a/docs/docs/06_sql_storage_sqlalchemy/08_retrieve_list_all_models/start/.flaskenv b/docs/docs/06_sql_storage_sqlalchemy/08_retrieve_list_all_models/start/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/06_sql_storage_sqlalchemy/08_retrieve_list_all_models/start/.flaskenv
+++ b/docs/docs/06_sql_storage_sqlalchemy/08_retrieve_list_all_models/start/.flaskenv
@@ -1,2 +1,2 @@
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-FLASK_ENV=development
\ No newline at end of file
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\ No newline at end of file
diff --git a/docs/docs/06_sql_storage_sqlalchemy/09_delete_models_sqlalchemy/end/.flaskenv b/docs/docs/06_sql_storage_sqlalchemy/09_delete_models_sqlalchemy/end/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/06_sql_storage_sqlalchemy/09_delete_models_sqlalchemy/end/.flaskenv
+++ b/docs/docs/06_sql_storage_sqlalchemy/09_delete_models_sqlalchemy/end/.flaskenv
@@ -1,2 +1,2 @@
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\ No newline at end of file
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\ No newline at end of file
diff --git a/docs/docs/06_sql_storage_sqlalchemy/09_delete_models_sqlalchemy/start/.flaskenv b/docs/docs/06_sql_storage_sqlalchemy/09_delete_models_sqlalchemy/start/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/06_sql_storage_sqlalchemy/09_delete_models_sqlalchemy/start/.flaskenv
+++ b/docs/docs/06_sql_storage_sqlalchemy/09_delete_models_sqlalchemy/start/.flaskenv
@@ -1,2 +1,2 @@
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\ No newline at end of file
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\ No newline at end of file
diff --git a/docs/docs/07_sqlalchemy_many_to_many/02_one_to_many_review/end/.flaskenv b/docs/docs/07_sqlalchemy_many_to_many/02_one_to_many_review/end/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/07_sqlalchemy_many_to_many/02_one_to_many_review/end/.flaskenv
+++ b/docs/docs/07_sqlalchemy_many_to_many/02_one_to_many_review/end/.flaskenv
@@ -1,2 +1,2 @@
 FLASK_APP=app
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\ No newline at end of file
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\ No newline at end of file
diff --git a/docs/docs/07_sqlalchemy_many_to_many/02_one_to_many_review/start/.flaskenv b/docs/docs/07_sqlalchemy_many_to_many/02_one_to_many_review/start/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/07_sqlalchemy_many_to_many/02_one_to_many_review/start/.flaskenv
+++ b/docs/docs/07_sqlalchemy_many_to_many/02_one_to_many_review/start/.flaskenv
@@ -1,2 +1,2 @@
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\ No newline at end of file
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\ No newline at end of file
diff --git a/docs/docs/07_sqlalchemy_many_to_many/03_many_to_many_relationships/end/.flaskenv b/docs/docs/07_sqlalchemy_many_to_many/03_many_to_many_relationships/end/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/07_sqlalchemy_many_to_many/03_many_to_many_relationships/end/.flaskenv
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@@ -1,2 +1,2 @@
 FLASK_APP=app
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\ No newline at end of file
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\ No newline at end of file
diff --git a/docs/docs/07_sqlalchemy_many_to_many/03_many_to_many_relationships/start/.flaskenv b/docs/docs/07_sqlalchemy_many_to_many/03_many_to_many_relationships/start/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/07_sqlalchemy_many_to_many/03_many_to_many_relationships/start/.flaskenv
+++ b/docs/docs/07_sqlalchemy_many_to_many/03_many_to_many_relationships/start/.flaskenv
@@ -1,2 +1,2 @@
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\ No newline at end of file
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\ No newline at end of file
diff --git a/docs/docs/08_flask_jwt_extended/04_flask_jwt_extended_setup/end/.flaskenv b/docs/docs/08_flask_jwt_extended/04_flask_jwt_extended_setup/end/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/08_flask_jwt_extended/04_flask_jwt_extended_setup/end/.flaskenv
+++ b/docs/docs/08_flask_jwt_extended/04_flask_jwt_extended_setup/end/.flaskenv
@@ -1,2 +1,2 @@
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\ No newline at end of file
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\ No newline at end of file
diff --git a/docs/docs/08_flask_jwt_extended/04_flask_jwt_extended_setup/start/.flaskenv b/docs/docs/08_flask_jwt_extended/04_flask_jwt_extended_setup/start/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/08_flask_jwt_extended/04_flask_jwt_extended_setup/start/.flaskenv
+++ b/docs/docs/08_flask_jwt_extended/04_flask_jwt_extended_setup/start/.flaskenv
@@ -1,2 +1,2 @@
 FLASK_APP=app
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\ No newline at end of file
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\ No newline at end of file
diff --git a/docs/docs/08_flask_jwt_extended/05_user_model_and_schema/end/.flaskenv b/docs/docs/08_flask_jwt_extended/05_user_model_and_schema/end/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/08_flask_jwt_extended/05_user_model_and_schema/end/.flaskenv
+++ b/docs/docs/08_flask_jwt_extended/05_user_model_and_schema/end/.flaskenv
@@ -1,2 +1,2 @@
 FLASK_APP=app
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\ No newline at end of file
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\ No newline at end of file
diff --git a/docs/docs/08_flask_jwt_extended/05_user_model_and_schema/start/.flaskenv b/docs/docs/08_flask_jwt_extended/05_user_model_and_schema/start/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/08_flask_jwt_extended/05_user_model_and_schema/start/.flaskenv
+++ b/docs/docs/08_flask_jwt_extended/05_user_model_and_schema/start/.flaskenv
@@ -1,2 +1,2 @@
 FLASK_APP=app
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\ No newline at end of file
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\ No newline at end of file
diff --git a/docs/docs/08_flask_jwt_extended/06_registering_users_rest_api/end/.flaskenv b/docs/docs/08_flask_jwt_extended/06_registering_users_rest_api/end/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/08_flask_jwt_extended/06_registering_users_rest_api/end/.flaskenv
+++ b/docs/docs/08_flask_jwt_extended/06_registering_users_rest_api/end/.flaskenv
@@ -1,2 +1,2 @@
 FLASK_APP=app
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\ No newline at end of file
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\ No newline at end of file
diff --git a/docs/docs/08_flask_jwt_extended/06_registering_users_rest_api/start/.flaskenv b/docs/docs/08_flask_jwt_extended/06_registering_users_rest_api/start/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/08_flask_jwt_extended/06_registering_users_rest_api/start/.flaskenv
+++ b/docs/docs/08_flask_jwt_extended/06_registering_users_rest_api/start/.flaskenv
@@ -1,2 +1,2 @@
 FLASK_APP=app
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\ No newline at end of file
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\ No newline at end of file
diff --git a/docs/docs/08_flask_jwt_extended/07_login_users_rest_api/end/.flaskenv b/docs/docs/08_flask_jwt_extended/07_login_users_rest_api/end/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/08_flask_jwt_extended/07_login_users_rest_api/end/.flaskenv
+++ b/docs/docs/08_flask_jwt_extended/07_login_users_rest_api/end/.flaskenv
@@ -1,2 +1,2 @@
 FLASK_APP=app
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\ No newline at end of file
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\ No newline at end of file
diff --git a/docs/docs/08_flask_jwt_extended/07_login_users_rest_api/start/.flaskenv b/docs/docs/08_flask_jwt_extended/07_login_users_rest_api/start/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/08_flask_jwt_extended/07_login_users_rest_api/start/.flaskenv
+++ b/docs/docs/08_flask_jwt_extended/07_login_users_rest_api/start/.flaskenv
@@ -1,2 +1,2 @@
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\ No newline at end of file
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\ No newline at end of file
diff --git a/docs/docs/08_flask_jwt_extended/08_protect_resources_with_jwt_required/end/.flaskenv b/docs/docs/08_flask_jwt_extended/08_protect_resources_with_jwt_required/end/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/08_flask_jwt_extended/08_protect_resources_with_jwt_required/end/.flaskenv
+++ b/docs/docs/08_flask_jwt_extended/08_protect_resources_with_jwt_required/end/.flaskenv
@@ -1,2 +1,2 @@
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\ No newline at end of file
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\ No newline at end of file
diff --git a/docs/docs/08_flask_jwt_extended/08_protect_resources_with_jwt_required/start/.flaskenv b/docs/docs/08_flask_jwt_extended/08_protect_resources_with_jwt_required/start/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/08_flask_jwt_extended/08_protect_resources_with_jwt_required/start/.flaskenv
+++ b/docs/docs/08_flask_jwt_extended/08_protect_resources_with_jwt_required/start/.flaskenv
@@ -1,2 +1,2 @@
 FLASK_APP=app
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\ No newline at end of file
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\ No newline at end of file
diff --git a/docs/docs/08_flask_jwt_extended/09_jwt_claims_and_authorization/end/.flaskenv b/docs/docs/08_flask_jwt_extended/09_jwt_claims_and_authorization/end/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/08_flask_jwt_extended/09_jwt_claims_and_authorization/end/.flaskenv
+++ b/docs/docs/08_flask_jwt_extended/09_jwt_claims_and_authorization/end/.flaskenv
@@ -1,2 +1,2 @@
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\ No newline at end of file
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\ No newline at end of file
diff --git a/docs/docs/08_flask_jwt_extended/09_jwt_claims_and_authorization/start/.flaskenv b/docs/docs/08_flask_jwt_extended/09_jwt_claims_and_authorization/start/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/08_flask_jwt_extended/09_jwt_claims_and_authorization/start/.flaskenv
+++ b/docs/docs/08_flask_jwt_extended/09_jwt_claims_and_authorization/start/.flaskenv
@@ -1,2 +1,2 @@
 FLASK_APP=app
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\ No newline at end of file
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\ No newline at end of file
diff --git a/docs/docs/08_flask_jwt_extended/10_logout_users_rest_api/end/.flaskenv b/docs/docs/08_flask_jwt_extended/10_logout_users_rest_api/end/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/08_flask_jwt_extended/10_logout_users_rest_api/end/.flaskenv
+++ b/docs/docs/08_flask_jwt_extended/10_logout_users_rest_api/end/.flaskenv
@@ -1,2 +1,2 @@
 FLASK_APP=app
-FLASK_ENV=development
\ No newline at end of file
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\ No newline at end of file
diff --git a/docs/docs/08_flask_jwt_extended/10_logout_users_rest_api/start/.flaskenv b/docs/docs/08_flask_jwt_extended/10_logout_users_rest_api/start/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/08_flask_jwt_extended/10_logout_users_rest_api/start/.flaskenv
+++ b/docs/docs/08_flask_jwt_extended/10_logout_users_rest_api/start/.flaskenv
@@ -1,2 +1,2 @@
 FLASK_APP=app
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\ No newline at end of file
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\ No newline at end of file
diff --git a/docs/docs/08_flask_jwt_extended/12_token_refreshing_flask_jwt_extended/end/.flaskenv b/docs/docs/08_flask_jwt_extended/12_token_refreshing_flask_jwt_extended/end/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/08_flask_jwt_extended/12_token_refreshing_flask_jwt_extended/end/.flaskenv
+++ b/docs/docs/08_flask_jwt_extended/12_token_refreshing_flask_jwt_extended/end/.flaskenv
@@ -1,2 +1,2 @@
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\ No newline at end of file
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\ No newline at end of file
diff --git a/docs/docs/08_flask_jwt_extended/12_token_refreshing_flask_jwt_extended/start/.flaskenv b/docs/docs/08_flask_jwt_extended/12_token_refreshing_flask_jwt_extended/start/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/08_flask_jwt_extended/12_token_refreshing_flask_jwt_extended/start/.flaskenv
+++ b/docs/docs/08_flask_jwt_extended/12_token_refreshing_flask_jwt_extended/start/.flaskenv
@@ -1,2 +1,2 @@
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\ No newline at end of file
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\ No newline at end of file
diff --git a/docs/docs/12_task_queues_emails/01_send_emails_python_mailgun/end/.flaskenv b/docs/docs/12_task_queues_emails/01_send_emails_python_mailgun/end/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/12_task_queues_emails/01_send_emails_python_mailgun/end/.flaskenv
+++ b/docs/docs/12_task_queues_emails/01_send_emails_python_mailgun/end/.flaskenv
@@ -1,2 +1,2 @@
 FLASK_APP=app
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\ No newline at end of file
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\ No newline at end of file
diff --git a/docs/docs/12_task_queues_emails/01_send_emails_python_mailgun/start/.flaskenv b/docs/docs/12_task_queues_emails/01_send_emails_python_mailgun/start/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/12_task_queues_emails/01_send_emails_python_mailgun/start/.flaskenv
+++ b/docs/docs/12_task_queues_emails/01_send_emails_python_mailgun/start/.flaskenv
@@ -1,2 +1,2 @@
 FLASK_APP=app
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\ No newline at end of file
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\ No newline at end of file
diff --git a/docs/docs/12_task_queues_emails/02_send_email_user_registration/end/.flaskenv b/docs/docs/12_task_queues_emails/02_send_email_user_registration/end/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/12_task_queues_emails/02_send_email_user_registration/end/.flaskenv
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@@ -1,2 +1,2 @@
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\ No newline at end of file
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\ No newline at end of file
diff --git a/docs/docs/12_task_queues_emails/02_send_email_user_registration/start/.flaskenv b/docs/docs/12_task_queues_emails/02_send_email_user_registration/start/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/12_task_queues_emails/02_send_email_user_registration/start/.flaskenv
+++ b/docs/docs/12_task_queues_emails/02_send_email_user_registration/start/.flaskenv
@@ -1,2 +1,2 @@
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\ No newline at end of file
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\ No newline at end of file
diff --git a/docs/docs/12_task_queues_emails/03_what_is_task_queue/assets/queues.drawio.png b/docs/docs/12_task_queues_emails/03_what_is_task_queue/assets/queues.drawio.png
index 16f44a7f..2ee2b414 100644
Binary files a/docs/docs/12_task_queues_emails/03_what_is_task_queue/assets/queues.drawio.png and b/docs/docs/12_task_queues_emails/03_what_is_task_queue/assets/queues.drawio.png differ
diff --git a/docs/docs/12_task_queues_emails/04_populate_rq_task_queue/end/.flaskenv b/docs/docs/12_task_queues_emails/04_populate_rq_task_queue/end/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/12_task_queues_emails/04_populate_rq_task_queue/end/.flaskenv
+++ b/docs/docs/12_task_queues_emails/04_populate_rq_task_queue/end/.flaskenv
@@ -1,2 +1,2 @@
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\ No newline at end of file
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\ No newline at end of file
diff --git a/docs/docs/12_task_queues_emails/04_populate_rq_task_queue/start/.flaskenv b/docs/docs/12_task_queues_emails/04_populate_rq_task_queue/start/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/12_task_queues_emails/04_populate_rq_task_queue/start/.flaskenv
+++ b/docs/docs/12_task_queues_emails/04_populate_rq_task_queue/start/.flaskenv
@@ -1,2 +1,2 @@
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\ No newline at end of file
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\ No newline at end of file
diff --git a/docs/docs/12_task_queues_emails/05_rq_background_worker/end/.flaskenv b/docs/docs/12_task_queues_emails/05_rq_background_worker/end/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/12_task_queues_emails/05_rq_background_worker/end/.flaskenv
+++ b/docs/docs/12_task_queues_emails/05_rq_background_worker/end/.flaskenv
@@ -1,2 +1,2 @@
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\ No newline at end of file
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\ No newline at end of file
diff --git a/docs/docs/12_task_queues_emails/05_rq_background_worker/start/.flaskenv b/docs/docs/12_task_queues_emails/05_rq_background_worker/start/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/12_task_queues_emails/05_rq_background_worker/start/.flaskenv
+++ b/docs/docs/12_task_queues_emails/05_rq_background_worker/start/.flaskenv
@@ -1,2 +1,2 @@
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\ No newline at end of file
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\ No newline at end of file
diff --git a/docs/docs/12_task_queues_emails/06_sending_html_emails/end/.flaskenv b/docs/docs/12_task_queues_emails/06_sending_html_emails/end/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/12_task_queues_emails/06_sending_html_emails/end/.flaskenv
+++ b/docs/docs/12_task_queues_emails/06_sending_html_emails/end/.flaskenv
@@ -1,2 +1,2 @@
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\ No newline at end of file
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\ No newline at end of file
diff --git a/docs/docs/12_task_queues_emails/06_sending_html_emails/start/.flaskenv b/docs/docs/12_task_queues_emails/06_sending_html_emails/start/.flaskenv
index 75473901..ccb3106e 100644
--- a/docs/docs/12_task_queues_emails/06_sending_html_emails/start/.flaskenv
+++ b/docs/docs/12_task_queues_emails/06_sending_html_emails/start/.flaskenv
@@ -1,2 +1,2 @@
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\ No newline at end of file
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\ No newline at end of file
diff --git a/project/03-items-stores-smorest/.flaskenv b/project/03-items-stores-smorest/.flaskenv
index 75473901..ccb3106e 100644
--- a/project/03-items-stores-smorest/.flaskenv
+++ b/project/03-items-stores-smorest/.flaskenv
@@ -1,2 +1,2 @@
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\ No newline at end of file
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\ No newline at end of file
diff --git a/project/04-items-stores-smorest-sqlalchemy/.flaskenv b/project/04-items-stores-smorest-sqlalchemy/.flaskenv
index 75473901..ccb3106e 100644
--- a/project/04-items-stores-smorest-sqlalchemy/.flaskenv
+++ b/project/04-items-stores-smorest-sqlalchemy/.flaskenv
@@ -1,2 +1,2 @@
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\ No newline at end of file
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\ No newline at end of file
diff --git a/project/05-add-many-to-many/.flaskenv b/project/05-add-many-to-many/.flaskenv
index 75473901..ccb3106e 100644
--- a/project/05-add-many-to-many/.flaskenv
+++ b/project/05-add-many-to-many/.flaskenv
@@ -1,2 +1,2 @@
 FLASK_APP=app
-FLASK_ENV=development
\ No newline at end of file
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\ No newline at end of file
diff --git a/project/06-add-db-migrations/.flaskenv b/project/06-add-db-migrations/.flaskenv
index 75473901..ccb3106e 100644
--- a/project/06-add-db-migrations/.flaskenv
+++ b/project/06-add-db-migrations/.flaskenv
@@ -1,2 +1,2 @@
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-FLASK_ENV=development
\ No newline at end of file
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\ No newline at end of file
diff --git a/project/using-flask-restful/.flaskenv b/project/using-flask-restful/.flaskenv
index 75473901..ccb3106e 100644
--- a/project/using-flask-restful/.flaskenv
+++ b/project/using-flask-restful/.flaskenv
@@ -1,2 +1,2 @@
 FLASK_APP=app
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\ No newline at end of file
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\ No newline at end of file
diff --git a/project/using-flask-restx/.flaskenv b/project/using-flask-restx/.flaskenv
index 75473901..ccb3106e 100644
--- a/project/using-flask-restx/.flaskenv
+++ b/project/using-flask-restx/.flaskenv
@@ -1,2 +1,2 @@
 FLASK_APP=app
-FLASK_ENV=development
\ No newline at end of file
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\ No newline at end of file
diff --git a/project/using-flask-smorest/.flaskenv b/project/using-flask-smorest/.flaskenv
index 75473901..ccb3106e 100644
--- a/project/using-flask-smorest/.flaskenv
+++ b/project/using-flask-smorest/.flaskenv
@@ -1,2 +1,2 @@
 FLASK_APP=app
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\ No newline at end of file
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\ No newline at end of file