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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 best_prefix(bytes, system=NIST):
 """Return a bitmath instance representing the best human-readable representation of the number of bytes given by ``bytes``. In addition to a numeric type, the ``bytes`` parameter may also be a bitmath type. Optionally select a preferred unit system by specifying the ``system`` keyword. Choices for ``system`` are ``bitmath.NIST`` (default) and ``bitmath.SI``. Basically a shortcut for: Or: """

    if isinstance(bytes, Bitmath):
        value = bytes.bytes
    else:
        value = bytes
    return Byte(value).best_prefix(system=system)