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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 child(self, path):
 """ Override the base implementation to inject the share ID our constructor was passed. """

        if self._shareID is not None:
            self = url.URL.child(self, self._shareID)
            self._shareID = None
        return url.URL.child(self, path)