Update coding style after pycodestyle 2.1.0

In pycodestyle 2.1.0, E305 was introduced, which requires two blank
lines after top level declarations, too.

See https://github.com/PyCQA/pycodestyle/issues/400

See also #10689; thanks @stepshal for first mentioning this issue and
initial patches

devscripts/bash-completion.py

@@ -25,5 +25,6 @@ def build_completion(opt_parser):
         filled_template = template.replace("{{flags}}", " ".join(opts_flag))
         f.write(filled_template)
 
+
 parser = youtube_dl.parseOpts()[0]
 build_completion(parser)

devscripts/fish-completion.py

@@ -44,5 +44,6 @@ def build_completion(opt_parser):
     with open(FISH_COMPLETION_FILE, 'w') as f:
         f.write(filled_template)
 
+
 parser = youtube_dl.parseOpts()[0]
 build_completion(parser)

devscripts/generate_aes_testdata.py

@@ -23,6 +23,7 @@ def openssl_encode(algo, key, iv):
     out, _ = prog.communicate(secret_msg)
     return out
 
+
 iv = key = [0x20, 0x15] + 14 * [0]
 
 r = openssl_encode('aes-128-cbc', key, iv)

devscripts/gh-pages/update-sites.py

@@ -32,5 +32,6 @@ def main():
     with open('supportedsites.html', 'w', encoding='utf-8') as sitesf:
         sitesf.write(template)
 
+
 if __name__ == '__main__':
     main()

devscripts/make_contributing.py

@@ -28,5 +28,6 @@ def main():
     with io.open(outfile, 'w', encoding='utf-8') as outf:
         outf.write(out)
 
+
 if __name__ == '__main__':
     main()

devscripts/make_lazy_extractors.py

@@ -59,6 +59,7 @@ def build_lazy_ie(ie, name):
         s += make_valid_template.format(valid_url=ie._make_valid_url())
     return s
 
+
 # find the correct sorting and add the required base classes so that sublcasses
 # can be correctly created
 classes = _ALL_CLASSES[:-1]

devscripts/make_supportedsites.py

@@ -41,5 +41,6 @@ def main():
     with io.open(outfile, 'w', encoding='utf-8') as outf:
         outf.write(out)
 
+
 if __name__ == '__main__':
     main()

devscripts/prepare_manpage.py

@@ -74,5 +74,6 @@ def filter_options(readme):
 
     return ret
 
+
 if __name__ == '__main__':
     main()

devscripts/zsh-completion.py

@@ -44,5 +44,6 @@ def build_completion(opt_parser):
     with open(ZSH_COMPLETION_FILE, "w") as f:
         f.write(template)
 
+
 parser = youtube_dl.parseOpts()[0]
 build_completion(parser)

test/test_InfoExtractor.py

@@ -84,5 +84,6 @@ class TestInfoExtractor(unittest.TestCase):
         self.assertRaises(ExtractorError, self.ie._download_json, uri, None)
         self.assertEqual(self.ie._download_json(uri, None, fatal=False), None)
 
+
 if __name__ == '__main__':
     unittest.main()