AttributeError: module 'vertica_sdk' has no attribute 'UDSource'

Question

I try to write a parser for vertica in python. But i get this error message.

class MyParser(vertica_sdk.UDSource):
    def __init__(self):
            pass
    def setup(srvInterface, returnType):
            pass
    def process(self, srvInterface, inputbuffer, inputstate, streamwriter):
            print("1")