Catching Errors

[Alienspecimen]

I am learning about try/catch mechanism and do not understand how the following program works:

import random

def test2():
    i = input('i ?\n')
    j = input('j ?\n')
    try:
        i = float(i)
        j = float(j)
        print(i, j, i/j) # we try it
    except ZeroDivisionError: # in case of division by zero
        print('j should not be equal to 0.0\n')
        test(2) #recursion
    except ValueError: # in case where i or j cannot be casted
        print('enter integers or floats\n')
        test2()


test2()

More specifically, how does it know which except statement to call? There isn't a statement such an if/else statement for example that would direct the code to execute the correct one. Something like if there is a division by zero print "j should not be equal to 0.0" else print "enter integers or floats"

Thanks in advance.

---

Nevermind,

Later in the material it was stated that these are standard exceptions. I apologize for posting the question.

[Larz60+]

The ValueError and ZeroDivisionError are names associated with specific exceptions.
When an exception is thrown, the except clause looks at the name, and if it matches, executes the except clause.