3、python布尔类型和条件表达式

使用布尔值进行分支逻辑！

1.布尔类型

Python有一种称为bool的变量类型。它有两个可能的值：True和False。

In [1]:

x = True
print(x)
print(type(x))
True
<class 'bool'>

除了直接在代码中使用True或False之外，我们通常通过布尔运算符获取布尔值。这些运算符用于回答是/否问题。让我们来看一些这些运算符。

1.1比较运算

Operation	Description		Operation	Description
a == b	a equal to b		a != b	a not equal to b
a < b	a less than b		a > b	a greater than b
a <= b	a less than or equal to b		a >= b	a greater than or equal to b

In [2]:

def can_run_for_president(age):
    """Can someone of the given age run for president in the US?"""
    # The US Constitution says you must be at least 35 years old
    return age >= 35

print("Can a 19-year-old run for president?", can_run_for_president(19))
print("Can a 45-year-old run for president?", can_run_for_president(45))
Can a 19-year-old run for president? False
Can a 45-year-old run for president?