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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 _call(self, resource_url, params=None):
 """ Calls the Marvel API endpoint :param resource_url: url slug of the resource :type resource_url: str :param params: query params to add to endpoint :type params: str :returns: response -- Requests response """

        
        url = "%s%s" % (self._endpoint(), resource_url)
        if params:
            url += "?%s&%s" % (params, self._auth())
        else:
            url += "?%s" % self._auth()
        return requests.get(url)