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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 _fix_evidence_text(txt):
 """Eliminate some symbols to have cleaner supporting text."""

    txt = re.sub('[ ]?\( xref \)', '', txt)
    # This is to make [ xref ] become [] to match the two readers
    txt = re.sub('\[ xref \]', '[]', txt)
    txt = re.sub('[\(]?XREF_BIBR[\)]?[,]?', '', txt)
    txt = re.sub('[\(]?XREF_FIG[\)]?[,]?', '', txt)
    txt = re.sub('[\(]?XREF_SUPPLEMENT[\)]?[,]?', '', txt)
    txt = txt.strip()
    return txt