def valid(self):
    if (not self.value):
        return True
    if ((not self.value.startswith('http://')) and (not self.value.startswith('https://'))):
        return 'Needs to start with http:// or https://'
    else:
        return True
def valid(self):
    if (not self.value):
        return True
    if ((not self.value.startswith('http://')) and (not self.value.startswith('https://'))):
        return 'Needs to start with http:// or https://'
    else:
        return True