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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 _get_signature(self):
 """ Returns a 32-character hexadecimal md5 hash of the signature string. """


        keys = list(self.params.keys())

        keys.sort()

        string = ""

        for name in keys:
            string += name
            string += self.params[name]

        string += self.api_secret

        return md5(string)