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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 charge(self, data):
 """Second stage of an OPR request"""

        token = data.get("token", self._response["token"])
        data = {
            "token": token,
            "confirm_token": data.get("confirm_token")
        }
        return self._process('opr/charge', data)