docs: def p_static_var(p):
      '''static_var : VARIABLE EQUALS static_scalar
                    | VARIABLE'''
      if len(p) == 4:
          p[0] = ast.StaticVariable(p[1], p[3], lineno=p.lineno(1))
      else:
          p[0] = ast.StaticVariable(p[1], None, lineno=p.lineno(1))