'IRC PART command removes a user from an IRC channel.'

def test_part(self):

    self.proto.makeConnection(self.transport)
    self.proto.dataReceived(':alice1    JOIN    #group1\r\n')
    self.assertIn('group1', self.proto._ingroups['alice1'])
    self.assertNotIn('group2', self.proto._ingroups['alice1'])
    self.proto.dataReceived(':alice    PART    #group1\r\n')
    self.proto.dataReceived(':alice1    PART    #group1\r\n')
    self.proto.dataReceived(':alice1    PART    #group2\r\n')
    self.assertNotIn('group1', self.proto._ingroups['alice1'])
    self.assertNotIn('group2', self.proto._ingroups['alice1'])
