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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 embeddedFileAdd(self, buffer, name, filename=None, ufilename=None, desc=None):
 """Embed a new file."""


        if self.isClosed or self.isEncrypted:
            raise ValueError("operation illegal for closed / encrypted doc")


        return _fitz.Document_embeddedFileAdd(self, buffer, name, filename, ufilename, desc)