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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 text(self, text):
 """ process a pyth text and return the formatted string """

        ret = u"".join(text.content)
        if 'url' in text.properties:
            return u"`%s`_" % ret
        if 'bold' in text.properties:
            return u"**%s**" % ret
        if 'italic' in text.properties:
            return u"*%s*" % ret
        if 'sub' in text.properties:
            return ur"\ :sub:`%s`\ " % ret
        if 'super' in text.properties:
            return ur"\ :sup:`%s`\ " % ret
        return ret