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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 set(self, child, min_occurs=1, max_occurs=1):
 """Set the schema for the sequence children. @param child: The schema that children must match. @param min_occurs: The minimum number of children the sequence must have. @param max_occurs: The maximum number of children the sequence can have. """

        if isinstance(child, LeafSchema):
            raise RuntimeError("Sequence can't have leaf children")
        if self.child is not None:
            raise RuntimeError("Sequence has already a child")
        if min_occurs is None or max_occurs is None:
            raise RuntimeError("Sequence node without min or max")
        if isinstance(child, LeafSchema):
            raise RuntimeError("Sequence node with leaf child type")
        if not child.tag == "item":
            raise RuntimeError("Sequence node with bad child tag")

        self.child = child
        self.min_occurs = min_occurs
        self.max_occurs = max_occurs
        return child