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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_http_args(self, params):
 """ Return a copy of the http_args Adds auth headers and 'source_id', merges in params. """

        # Add the auth headers to any other headers
        headers = self.http_args.get('headers', {})
        if self.auth is not None:
            auth_headers = self.auth.get_headers()
            headers.update(auth_headers)

        # build new http args with these headers
        http_args = self.http_args.copy()
        if self._source_id is not None:
            headers['source_id'] = self._source_id
        http_args['headers'] = headers

        # Merge in any params specified by the caller.
        merged_params = http_args.get('params', {})
        merged_params.update(params)
        http_args['params'] = merged_params
        return http_args