def set_child_node(self, name, node):
assert isinstance(node, TreeMapNode)<EOL>self._nodes[name] = node<EOL>node.set_parent(self)<EOL>
Add one child node to this node.

Args:
    name (str): Name of the child.
    node (TreeMapNode): Node to add.

Warning:
    No test is done to see whether or not a node was already attached with that name. If this is the case, the
    new node takes the place of the old one that is now unreachable. See :meth:`set_unique_child_node`.