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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 octocat(self, say=None):
 """Returns an easter egg of the API. :params str say: (optional), pass in what you'd like Octocat to say :returns: ascii art of Octocat """

        url = self._build_url('octocat')
        req = self._get(url, params={'s': say})
        return req.content if req.ok else ''