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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def listar_healtchcheck_expect_distinct(self):
 """Get all expect_string. :return: Dictionary with the following structure: :: {'healthcheck_expect': [ 'expect_string': < expect_string >, :raise InvalidParameterError: Identifier is null and invalid. :raise DataBaseError: Networkapi failed to access the database. :raise XMLError: Networkapi failed to generate the XML response. """


        url = 'healthcheckexpect/distinct/busca/'

        code, xml = self.submit(None, 'GET', url)

        return self.response(code, xml)