fixed comparison operator

Author: roy0424

pymysqlreplication/event.py

@@ -106,7 +106,7 @@ def __init__(self, from_packet, event_size, table_map, ctl_connection, **kwargs)
         self.gno = struct.unpack("<Q", self.packet.read(8))[0]
         self.lt_type = self.packet.read(1)[0]
 
-        if self.dbms is "mysql" and self.mysql_version >= (5, 7):
+        if self.dbms == "mysql" and self.mysql_version >= (5, 7):
             self.last_committed = struct.unpack("<Q", self.packet.read(8))[0]
             self.sequence_number = struct.unpack("<Q", self.packet.read(8))[0]