格式化输出的方法：%、.format()、f

a = '123'
a1 = '456'
a2 = '789'

%占位符

text = "a=%s"%a
text1 = "a=%s,a1=%s,a2=%s"%(a, a1, a2)
print(text)
print(text1)

.format()方法

text = "a={}".format(a)
text1 = "a={},a1={},a2={}".format(a, a1, a2)  # 不指定下标，按顺序传

text2 = "a={0},a1={1},a2={2}".format(a, a1, a2)  # 指定下标传值

print(text)
print(text1)
print(text2)

f方法（推荐）：# 指定位置传指定值，代码简洁，不易出错

text = f'a={a}'
text1 = f'a={a},a1={a1},a2={a2}'
print(text)