def remove_child(self, child):
try:<EOL><INDENT>self.children.remove(child)<EOL><DEDENT>except ValueError as e:<EOL><INDENT>raise TreeError("<STR_LIT>")<EOL><DEDENT>else:<EOL><INDENT>child.up = None<EOL>return child<EOL><DEDENT>
Removes a child from this node (parent and child
nodes still exit but are no longer connected).