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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 to_fs_from_unicode(unic):

 """
 Return a byte string version of unic encoded using the file 
 system encoding.
 """

    if is_unicode(unic):
        try:
            string = unic.encode(FS_ENCODING)
        except (UnicodeError, TypeError):
            pass
        else:
            return string
    return unic