parameters: (self, p)
docstring: array_arg : 
                       | arg
docstring_summary: array_arg : 
                       | arg
docstring_tokens: array_arg : | arg
function: def p_array_arg (self, p):
          '''array_arg : 
                       | arg'''
          if len (p) == 1: p[0] = None
          else: p[0] = p[1]
function_tokens: def p_array_arg ( self , p ) : if len ( p ) == 1 : p [ 0 ] = None else : p [ 0 ] = p [ 1 ]