Grammar

gistfile1.py

def p_exp_int(p):
    'exp : INT'
    p[0] = ast.Num(p[1], p.lineno(1))

def p_exp_bool_true(p):
    'exp : TRUE'
    p[0] = ast.Bool(True, p.lineno(1))

def p_exp_bool_false(p):
    'exp : FALSE'
    p[0] = ast.Bool(False, p.lineno(1))

...

def p_exp_binary(p):
    '''
    exp : exp PLUS exp
        | exp MINUS exp
        | exp STAR exp
        | exp SLASH exp
        | exp MOD exp
        | exp EQ exp
        | exp NEQ exp
        | exp GT exp
        | exp LT exp
        | exp GE exp
        | exp LE exp
    '''
    p[0] = ast.BinOp(p[1], p[2], p[3], p.lineno(3))