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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 encrypt_to(self, f, mac_bytes=10):
 """ Returns a file like object `ef'. Anything written to `ef' will be encrypted for this pubkey and written to `f'. """

        ctx = EncryptionContext(f, self.p, mac_bytes)
        yield ctx
        ctx.finish()