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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 _load_background_color(self):
 """ Loads the data related to the fill color """

        url = self.build_url(self._endpoints.get('fill'))
        response = self.session.get(url)
        if not response:
            return None
        data = response.json()
        self._background_color = data.get('color', None)