def coerce(cls, string):
        """Create a :class:`Requirement` object from a given package spec."""
        match = re.match(cls.spec_regex, string)
        if not match:
            raise InvalidRequirementSpecError("could not parse requirement")
        package = match.group(1)
        if all(match.group(2, 3)):
            version = "".join(match.group(2, 3))
        else:
            version = None
        return cls(package, version)
def get_next(next_link=None):
            request = prepare_request(next_link)

            pipeline_response = self._client._pipeline.run(request, stream=False, **kwargs)
            response = pipeline_response.http_response

            if response.status_code not in [200]:
                map_error(status_code=response.status_code, response=response, error_map=error_map)
                raise HttpResponseError(response=response, error_format=ARMErrorFormat)

            return pipeline_response