Can any one explain me assert and raise in Python ? | Sololearn: Learn to code for FREE!
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Can any one explain me assert and raise in Python ?

It more confused me plse help me Friends

3rd Jan 2019, 7:23 AM
Programmer Raja
Programmer Raja - avatar
3 Answers
+ 8
"assert" is used to assert that a certain condition is true. If it isn't, an AssertionError will be raised. You can add a string that is displayed together with the error message: a = 25 assert 0 <= a <= 50, "Invalid value" # output: (none, assertion is True) a = 25 assert 0 <= a <= 20, "Invalid value" # result: AssertionError: Invalid value asserts should be used with care, because some interpreters have settings to simply ignore assert statements. In this case, even if the assert statement is False, nothing will happen. It's best to use them for debugging only. "raise" raises a predefined or self-made exception: a = 25 if a < 50: raise ValueError("Invalid value") # result: ValueError: Invalid value It can also be used within a try/except block to raise the error after you inspected it: try: print(25/0) except ZeroDivisionError: print('can\'t divide by zero') # this catches the error raise # this will raise the caught error # result: This will output "can't divide by zero" first and then raise a ZeroDivisionError
3rd Jan 2019, 9:12 AM
Anna
Anna - avatar
+ 2
You can define your own exception like this: class AgeError(Exception): pass # empty class raise AgeError('custom error message')
3rd Jan 2019, 12:22 PM
Anna
Anna - avatar
+ 1
Anna can you tell how we can raise our own error using class and raise plse like raise AgeError
3rd Jan 2019, 12:19 PM
Programmer Raja
Programmer Raja - avatar