I am new to python and Could someone please explain how this below code is working?

[kartheekdas]

a=True
try:
    assert a and not print("sucess"),"failure"
except Exception as e:
    print("e is",e)

Output is Sucess when a is True
and Output is Failure when a is False

Could someone please explain how this code is working in detail?

snippsat write Dec-19-2022, 04:25 PM:
Added code tag in your post,look at BBCode on how to use.

[deanhystad]

Calling a function returns a value. Calling print() always returns None. not None is True, so not print("sucess") is True.

In Python, A and B, B is only evaluated if A is truthy. In your code, A is a, and B is print("success")

"assert X, Y" raises AssertionError(Y) if X evaluates to something that is falsey. In your code "assert a and not print("sucess")" is X and "failure" is Y.

In an try/except:

try:
    body
except exception_type as excception_info:
    exception code

If an exception is raised while the body is executed, control jumps to the except. If the raised exception matches the exception type, the exception code is executed. Information associated with the exception can be passed as an argument (exception_info)

Putting them all together:
If a is True, then then print("success") is called to get the return value of the print() function. The expression "assert a and not print("sucess")" evaluates to True, so the assertion error is not raised.

If a is False, the print() function is not called, and AssertionError("failure") is raised.

If an AssertionError("failure" is raised, the exception code prints the exception info ("failure")

[kartheekdas]

got the answer,

assert a and not print("sucess"),"failure"
If 'a' is True, then python executes the next expression 'not print("sucess")'.
print("success") prints "success", and then returns None. not None is True(print(not None)), so the assert passes.
If 'a' is False, then python doesn't bother about executing the second part and the assert just fails.
When an assert fails it prints the message after the comma which is "failure"