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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_tokens(self, filters={}):
 """ Returns dict of tokens matching the provided filters """

        uri = 'tokens'

        if filters:
            filters = {'filters': json.dumps(filters)}
            uri += "?%s" % urllib.urlencode(filters, True)

        resp, body = self.get(uri)
        self.expected_success(200, resp.status)
        body = json.loads(body)
        return rest_client.ResponseBody(resp, body)