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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 __build_url(self, api_call, **kwargs):
 """Builds the api query"""

        kwargs['key'] = self.api_key
        if 'language' not in kwargs:
            kwargs['language'] = self.language
        if 'format' not in kwargs:
            kwargs['format'] = self.__format
        api_query = urlencode(kwargs)

        return "{0}{1}?{2}".format(urls.BASE_URL,
                                   api_call,
                                   api_query)