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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 decrypt(s, passphrase, curve='secp160r1', mac_bytes=10):
 """ Decrypts `s' with passphrase `passphrase' """

    curve = Curve.by_name(curve)
    privkey = curve.passphrase_to_privkey(passphrase)
    return privkey.decrypt(s, mac_bytes)