def get_node_sum(self, age=None):
if age is None:<EOL><INDENT>age = self.age<EOL><DEDENT>return age if self.comp == <NUM_LIT:1> else int((pow(self.comp, age+<NUM_LIT:1>) - <NUM_LIT:1>) / (self.comp - <NUM_LIT:1>))<EOL>
Get sum of all branches in the tree.

        Returns:
            int: The sum of all nodes grown until the age.