def _get_value(self, v):
    if isinstance(v, str):
        return "'{}'".format(v)
    elif (v is None):
        return 'NULL'
    else:
        return '{}'.format(v)
def _get_value(self, v):
    if isinstance(v, str):
        return "'{}'".format(v)
    elif (v is None):
        return 'NULL'
    else:
        return '{}'.format(v)