diff --git a/app/cafe.py b/app/cafe.py
new file mode 100644
index 00000000..f9e8c4a2
--- /dev/null
+++ b/app/cafe.py
@@ -0,0 +1,18 @@
+import datetime
+from app.errors import (NotVaccinatedError,
+                        OutdatedVaccineError,
+                        NotWearingMaskError)
+
+
+class Cafe:
+    def __init__(self, name: str) -> None:
+        self.name = name
+
+    def visit_cafe(self, visitor: dict) -> str:
+        if "vaccine" not in visitor:
+            raise NotVaccinatedError("You have to be vaccinated.")
+        elif visitor["vaccine"].get("expiration_date") < datetime.date.today():
+            raise OutdatedVaccineError("Your vaccine is expired.")
+        elif not visitor.get("wearing_a_mask"):
+            raise NotWearingMaskError("You have to be in mask.")
+        return f"Welcome to {self.name}"
diff --git a/app/errors.py b/app/errors.py
new file mode 100644
index 00000000..dbc06145
--- /dev/null
+++ b/app/errors.py
@@ -0,0 +1,14 @@
+class VaccineError(Exception):
+    pass
+
+
+class NotVaccinatedError(VaccineError):
+    pass
+
+
+class OutdatedVaccineError(VaccineError):
+    pass
+
+
+class NotWearingMaskError(Exception):
+    pass
diff --git a/app/main.py b/app/main.py
index fa56336e..d984f752 100644
--- a/app/main.py
+++ b/app/main.py
@@ -1 +1,16 @@
-# write your code here
+from app.cafe import Cafe
+from app.errors import VaccineError, NotWearingMaskError
+
+
+def go_to_cafe(friends: list[dict], cafe: Cafe) -> str:
+    masks_to_buy = 0
+    for friend in friends:
+        try:
+            cafe.visit_cafe(friend)
+        except NotWearingMaskError:
+            masks_to_buy += 1
+        except VaccineError:
+            return "All friends should be vaccinated"
+    if masks_to_buy:
+        return f"Friends should buy {masks_to_buy} masks"
+    return f"Friends can go to {cafe.name}"