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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 _str_replace(txt):
 """Makes a small text amenable to being used in a filename."""

        txt = txt.replace(",", "")
        txt = txt.replace(" ", "_")
        txt = txt.replace(":", "")
        txt = txt.replace(".", "")
        txt = txt.replace("/", "")
        txt = txt.replace("", "")
        return txt