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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 file_root_name(name):
 """ Returns the root name of a file from a full file path. It will not raise an error if the result is empty, but an warning will be issued. """

    base = os.path.basename(name)
    root = os.path.splitext(base)[0]
    if not root:
        warning = 'file_root_name returned an empty root name from \"{0}\"'
        log.warning(warning.format(name))
    return root