Execution Flow:

Initial State:
m is set to 0 globally

First Error:
When foo() is called without parameters, it raises a TypeError (missing required argument)
However, before that happens, the assert m!=0 statement is evaluated
Since m is 0, this raises an AssertionError
Exception Handling:
The AssertionError is not an ArithmeticError, so it's caught by the second except clause
This means m += 1 is executed first, making m = 1

Program Continues:
After the first exception is caught, the code continues running
The TypeError (missing argument) is also caught by the second except clause
This means m += 1 is executed again, making m = 2

Finally, the AssertionError triggers one more time, adding 1 more to m
This makes m = 3

Final Result
The value of m becomes 3 because:
First AssertionError: +1
TypeError from missing argument: +1
Second AssertionError: +1
Total: 1 + 1 + 1 = 3

This code raise the assertion error so this code only handle Arithmetic error and the code enters in except branch and the final result is 1.

Answer is erroneous:
m=0
def foo(n):
global m
assert m!=0
try:
return 1/n
except ArithmeticError:
raise ValueError
try:
foo()
except ArithmeticError:
m+=2
except:
m+=1
print(m)

print --> 1 on screen after execution