What is Python's equivalent of && (logical-and) in an if-statement?

Syntax specifics and evaluations

Python's and handles slightly differently than && in languages such as C and Java.

Short-circuit logic

Python bases its evaluation on short-circuit logic. If the left operand is False, Python does not evaluate the right operand.

Bitwise vs. logical operation

Don't mix up and with &. The first is a logical operator, the latter a bitwise operator.

Non-boolean and array types with logic

When evaluating non-boolean types or arrays using logical and, Python implicitly calls the __bool__ method. However, when using NumPy arrays, a ValueError might spring up.

The second logical operator

For logic that needs at least one condition to be true, use the or operator.

Traps and tricks

Incorrect use of logical operators can lead to either errors or headaches. These tips make your coding life easier:

Say no to bitwise in logic

Avoid using && or ||. Stick to the Pythonic way: and and or.

Clean and clear code

For write pythonic and crystal-clear code, obey the PEP 8 style guidelines. The four-space indentation is particularly helpful.

More logical magic

Compound and nested logical operations are on the Python-menu:

if (condition1 and condition2) or (condition3 and condition4):
    # ...when you want a fancy dinner and a movie night or pizza and a TV-show marathon.
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Even lists can be an operand for boolean evaluations thanks to Python's implicit bool calls!

Additional know-how

Non-Boolean operands

Python isn't picky. It can use and with non-Boolean types, unlike many strictly-typed languages.

Mutable subplot

Be careful when using mutable default arguments with and. It could lead to unexpected results.

Use short-circuiting

Short-circuiting can improve your program's performance. So place the faster or the likely-to-be-false condition first. The code evaluation won't reach the second operand if the first evaluates to False.