Use python Return the maximum branching factor (arity) of Tree t. @PARAM Tree t: tree to find the arity of @r type: int example: >>>arity(Tree(2, [Tree(3, Tree(4), Tree(5), Tree(7), Tree(6)])) def arity (t): Use python Return the maximum branching factor (arity) of Tree t. @PARAM Tree t: tree to find the arity of @r type: int example: >>>arity(Tree(2, [Tree(3, Tree(4), Tree(5), Tree(7), Tree(6)])) def arity (t)