Function with two loops

I want to make a function what must have 2 loops:

1. must check that at least 2 characters (letters) are inserted
2. if the two characters are in the form that the variable must receive at the end, the variable receives the correct orthographic form.

Here is my code (but it throws me in infinite loop) [Please be indulgent im a begginer (: ] :

def sede():
    while True:
        import re

        var_sede_0 = input("Sede : ")

        if re.match("([a-zA-Z]+.*?){2,}", var_sede_0):
            while True:
                if var_sede_0.lower() in 'torino (to)':
                    var_sede_0 = 'Torino (TO)'
                    break

                elif var_sede_0.lower() in 'reggio calabria (rc)':
                    var_sede_0 = 'Reggio Calabria (RC)'
                    break
                else:
                    print("sbagliato")
                    continue
            break
        else:
            print("formato sbagliato")
            continue


    return var_sede_0
var_sede = sede()

Answer

Your inner loop is the problem:

while True:
    if var_sede_0.lower() in 'torino (to)':
        var_sede_0 = 'Torino (TO)'
        break

    elif var_sede_0.lower() in 'reggio calabria (rc)':
        var_sede_0 = 'Reggio Calabria (RC)'
        break
    else:
        print("sbagliato")
        continue

Consider that nowhere in this loop do you take in new input, so var_sede_0 can never possibly change. Given that, if the first two predicates (if statements) evaluate to false, then you will be in an infinite loop printing out sbagliato. You can probably simply remove the while True (the inner one) and get to what you want.

It is key to note that break and continue really only affect the immediate while context that they are in – they will not ‘speak to’ the outer while loop.

You also probably do not want to be importing re on every loop. Move import re to the top of your file.