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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 _is_child(self, parent, child):
 # type: (str, str) -> bool """ Returns whether a key is strictly a child of another key. AoT siblings are not considered children of one another. """

        parent_parts = tuple(self._split_table_name(parent))
        child_parts = tuple(self._split_table_name(child))

        if parent_parts == child_parts:
            return False

        return parent_parts == child_parts[: len(parent_parts)]