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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 get_file(self):
 """ Calls GetCdnFileRequest and decrypts its bytes. Also ensures that the file hasn't been tampered. :return: the CdnFile result. """

        if self.cdn_file_hashes:
            cdn_hash = self.cdn_file_hashes.pop(0)
            cdn_file = self.client(GetCdnFileRequest(
                self.file_token, cdn_hash.offset, cdn_hash.limit
            ))
            cdn_file.bytes = self.cdn_aes.encrypt(cdn_file.bytes)
            self.check(cdn_file.bytes, cdn_hash)
        else:
            cdn_file = CdnFile(bytes(0))

        return cdn_file