def __init__(self, msg=None):
    self.msg = msg
    if (not self.msg):
        self.msg = 'Adding this session would result in a tweet longer than 140 characters.'
def __init__(self, msg=None):
    self.msg = msg
    if (not self.msg):
        self.msg = 'Adding this session would result in a tweet longer than 140 characters.'