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diff --git a/pylint/checkers/async.py b/pylint/checkers/async.py
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+# Copyright (c) 2003-2015 LOGILAB S.A. (Paris, FRANCE).
+# http://www.logilab.fr/ -- mailto:contact@logilab.fr
+# Copyright (c) 2009-2010 Arista Networks, Inc.
+#
+# This program is free software; you can redistribute it and/or modify it under
+# the terms of the GNU General Public License as published by the Free Software
+# Foundation; either version 2 of the License, or (at your option) any later
+# version.
+#
+# This program is distributed in the hope that it will be useful, but WITHOUT
+# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+# FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License along with
+# this program; if not, write to the Free Software Foundation, Inc.,
+# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+"""Checker for anything related to the async protocol (PEP 492)."""
+
+import astroid
+from astroid import exceptions
+from astroid import helpers
+
+from pylint import checkers
+from pylint.checkers import utils as checker_utils
+from pylint import interfaces
+from pylint import utils
+
+
+class AsyncChecker(checkers.BaseChecker):
+    __implements__ = interfaces.IAstroidChecker
+    name = 'async'
+    msgs = {
+        'E1700': ('Yield inside async function',
+                  'yield-inside-async-function',
+                  'Used when an `yield` or `yield from` statement is '
+                  'found inside an async function.',
+                  {'minversion': (3, 5)}),
+        'E1701': ("Async context manager '%s' doesn't implement __aenter__ and __aexit__.",
+                  'not-async-context-manager',
+                  'Used when an async context manager is used with an object '
+                  'that does not implement the async context management protocol.',
+                  {'minversion': (3, 5)}),
+    }
+
+    def open(self):
+        self._ignore_mixin_members = utils.get_global_option(self, 'ignore-mixin-members')
+
+    @checker_utils.check_messages('yield-inside-async-function')
+    def visit_asyncfunctiondef(self, node):
+        for child in node.nodes_of_class(astroid.Yield):
+            if child.scope() is node:
+                self.add_message('yield-inside-async-function', node=child)
+
+    @checker_utils.check_messages('not-async-context-manager')
+    def visit_asyncwith(self, node):
+        for ctx_mgr, _ in node.items:
+            infered = helpers.safe_infer(ctx_mgr)
+            if infered is None or infered is astroid.YES:
+                continue
+
+            if isinstance(infered, astroid.Instance):
+                try:
+                    infered.getattr('__aenter__')
+                    infered.getattr('__aexit__')
+                except exceptions.NotFoundError:
+                    if isinstance(infered, astroid.Instance):
+                        # If we do not know the bases of this class,
+                        # just skip it.
+                        if not helpers.has_known_bases(infered):
+                            continue
+                        # Just ignore mixin classes.
+                        if self._ignore_mixin_members:
+                            if infered.name[-5:].lower() == 'mixin':
+                                continue
+                else:
+                    continue
+
+            self.add_message('not-async-context-manager',
+                             node=node, args=(infered.name, ))
+
+
+def register(linter):
+    """required method to auto register this checker"""
+    linter.register_checker(AsyncChecker(linter))