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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 _list(self, path, dim_key=None, **kwargs):
 """Get a list of metrics."""

        url_str = self.base_url + path
        if dim_key and dim_key in kwargs:
            dim_str = self.get_dimensions_url_string(kwargs[dim_key])
            kwargs[dim_key] = dim_str

        if kwargs:
            url_str += '?%s' % parse.urlencode(kwargs, True)

        body = self.client.list(
            path=url_str
        )

        return self._parse_body(body)