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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 authenticate(self, password):
 """Decrypt document with a password."""

        if self.isClosed:
            raise ValueError("operation illegal for closed doc")

        val = _fitz.Document_authenticate(self, password)

        if val: # the doc is decrypted successfully and we init the outline
            self.isEncrypted = 0
            self.initData()
            self.thisown = True


        return val