Generalize deprecation avoidance

Author: myint

pep8.py

@@ -1314,6 +1314,13 @@ def _is_eol_token(token, _eol_token=_is_eol_token):
 _checks = {'physical_line': {}, 'logical_line': {}, 'tree': {}}
 
 
+def _get_parameters(function):
+    if sys.version_info >= (3, 3):
+        return list(inspect.signature(function).parameters)
+    else:
+        return inspect.getargspec(function)[0]
+
+
 def register_check(check, codes=None):
     """Register a new check object."""
     def _add_check(check, kind, codes, args):
@@ -1322,18 +1329,13 @@ def _add_check(check, kind, codes, args):
         else:
             _checks[kind][check] = (codes or [''], args)
     if inspect.isfunction(check):
-        args = inspect.getargspec(check)[0]
+        args = _get_parameters(check)
         if args and args[0] in ('physical_line', 'logical_line'):
             if codes is None:
                 codes = ERRORCODE_REGEX.findall(check.__doc__ or '')
             _add_check(check, args[0], codes, args)
     elif inspect.isclass(check):
-        if sys.version_info >= (3, 3):
-            parameters = list(inspect.signature(check.__init__).parameters)
-        else:
-            parameters = inspect.getargspec(check.__init__)[0]
-
-        if parameters[:2] == ['self', 'tree']:
+        if _get_parameters(check.__init__)[:2] == ['self', 'tree']:
             _add_check(check, 'tree', codes, None)