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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 print_subtree(self, fobj=sys.stdout, level=0):
 """Print this group node and the subtree rooted at it"""

        fobj.write("{}{!r}\n".format(" " * (level * 2), self))
        for child in self.get_children():
            child.print_subtree(fobj, level + 1)