Catch thrown OSError by python 3.7 when creating a connection (#1694)

Author: danjo133

kafka/conn.py

@@ -483,6 +483,9 @@ def _try_handshake(self):
         # old ssl in python2.6 will swallow all SSLErrors here...
         except (SSLWantReadError, SSLWantWriteError):
             pass
+        # python 3.7 throws OSError
+        except OSError:
+            pass
         except (SSLZeroReturnError, ConnectionError, SSLEOFError):
             log.warning('SSL connection closed by server during handshake.')
             self.close(Errors.KafkaConnectionError('SSL connection closed by server during handshake'))