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Python Booleans

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Python Booleans

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Booleans represent one of two values:

True or

False.

Boolean Values

In programming you often need to know if an expression is

True or

False. You can evaluate any expression in Python, and get one of two answers,

True or

False. When you compare two values, the expression is evaluated and Python returns the Boolean answer:

Example

print(10 > 9)
print(10 == 9)
print(10 < 9)

When you run a condition in an if statement, Python returns

True or

False

Example

Print a message based on whether the condition is

True or

False

Formula

a = 200 b = 33 if b > a:
print("b is greater than a")
else:
print("b is not greater than a")

Evaluate Values and Variables

The bool() function allows you to evaluate any value, and give you

True or

False in return,

Example

Evaluate a string and a number:

print(bool("Hello"))
print(bool(15))

Example

Evaluate two variables:

x = "Hello"

y = 15 print(bool(x))
print(bool(y))

Most Values are True

Almost any value is evaluated to

True if it has some sort of content.

Any string is

True, except empty strings.

Any number is

True, except . Any list, tuple, set, and dictionary are True, except empty ones.

Example

The following will return True:

bool("abc") bool(123) bool(["apple", "cherry", "banana"])

Some Values are False

In fact, there are not many values that evaluate to False, except empty values, such as (), [],

{},
"", the number

, and the value None.

And of course the value

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