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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 supplement_filesystem(old_size, user_cap=False):
 """Return new size accounting for the metadata."""

    new_size = old_size
    if user_cap:
        if old_size <= _GiB_to_Byte(1.5):
            new_size = _GiB_to_Byte(3)
        else:
            new_size += _GiB_to_Byte(1.5)
    return int(new_size)