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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 to_dict(self):
 """ Return a Python dict containing the important information about this Session Token. """

        return {'access_key': self.access_key,
                'secret_key': self.secret_key,
                'session_token': self.session_token,
                'expiration': self.expiration,
                'request_id': self.request_id}