Document GtidSet.

Author: darnuria

pymysqlreplication/gtid.py

@@ -307,6 +307,7 @@ def _to_gtid(element):
             self.gtids = [Gtid(x.strip(' \n')) for x in gtid_set.split(',')]
 
     def merge_gtid(self, gtid):
+        """Insert a Gtid in current GtidSet."""
         new_gtids = []
         for existing in self.gtids:
             if existing.sid == gtid.sid:
@@ -319,6 +320,8 @@ def merge_gtid(self, gtid):
 
     def __contains__(self, other):
         """
+        Test if self contains other, could be a GtidSet or a Gtid.
+
         Raises:
            - NotImplementedError other is not a GtidSet neither a Gtid,
             please convert it first to one of them