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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 fetch_access_token(self):
 """ Fetch access token"""

        return self._fetch_access_token(
            url='https://qyapi.weixin.qq.com/cgi-bin/gettoken',
            params={
                'corpid': self.corp_id,
                'corpsecret': self.secret
            }
        )