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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 save(self, filename):
 """ Store AEAD in a file. @param filename: File to create/overwrite @type filename: string """

        aead_f = open(filename, "wb")
        fmt = "< B I %is %is" % (pyhsm.defines.YSM_AEAD_NONCE_SIZE, len(self.data))
        version = 1
        packed = struct.pack(fmt, version, self.key_handle, self.nonce, self.data)
        aead_f.write(YHSM_AEAD_File_Marker + packed)
        aead_f.close()