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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 _get_from_cache(self, expr):
 """Obtain cached result, prepend with the keyname if necessary, and indent for the current level"""

        is_cached, res = super()._get_from_cache(expr)
        if is_cached:
            indent_str = "    " * self._print_level
            return True, indent(res, indent_str)
        else:
            return False,  None