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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 where(self, params):
 """Set a dict of parameters to be passed to the API when invoking this request. :param params: (dict) query parameters. :return: this :class:`.RequestArray` instance for convenience. """

        self.params = dict(self.params, **params)   # params overrides self.params
        return self