Cleanup ignore warnings (#89)

* Remove unused imports

* Do not use deprecated ignore_warnings

sh_scrapy/crawl.py

@@ -169,14 +169,14 @@ def _run_script(dist, script_name, namespace):
     exec(code, namespace, namespace)
 
 
-
 def _run_usercode(spider, args, apisettings_func,
                   log_handler=None, commands_module=None):
     try:
         from scrapy.exceptions import ScrapyDeprecationWarning
         from sh_scrapy.settings import populate_settings
 
-        with ignore_warnings(category=ScrapyDeprecationWarning):
+        with warnings.catch_warnings():
+            warnings.filterwarnings("ignore", category=ScrapyDeprecationWarning)
             settings = populate_settings(apisettings_func(), spider)
         if commands_module:
             settings.set('COMMANDS_MODULE', commands_module, priority=40)

sh_scrapy/extension.py

@@ -6,13 +6,11 @@
 import scrapy
 from scrapy import signals
 from scrapy import version_info as SCRAPY_VERSION_INFO
-from scrapy.exceptions import ScrapyDeprecationWarning
 from scrapy.exporters import PythonItemExporter
 from scrapy.http import Request
 from scrapy.utils.deprecate import create_deprecated_class
 
 from sh_scrapy import hsref
-from sh_scrapy.crawl import ignore_warnings
 from sh_scrapy.exceptions import SHScrapyDeprecationWarning
 from sh_scrapy.middlewares import HS_PARENT_ID_KEY, request_id_sequence
 from sh_scrapy.writer import pipe_writer