def _AppendFirstLeafTokenSubtype(node, subtype):
 if isinstance(node, pytree.Leaf):
  _AppendTokenSubtype(node, subtype)
  return
 _AppendFirstLeafTokenSubtype(node.children[0], subtype)

def _AppendFirstLeafTokenSubtype ( node , subtype ) : if isinstance ( node , pytree . Leaf ) : _AppendTokenSubtype ( node , subtype ) return _AppendFirstLeafTokenSubtype ( node . children [ 0 ] , subtype )
append the first leaf tokens subtypes .