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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 _format_unhashed_feature(name, hl_spaces, sep=' | '):
 # type: (List, bool, str) -> str """ Format feature name for hashed features. """

    return sep.join(
        format_signed(n, _format_single_feature, hl_spaces=hl_spaces)
        for n in name)