python - UnboundLocalError: local variable 'user_a' referenced before assignment -

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• python variable scope error 10 answers

i cannot figure out how make code below work. getting exception:

unboundlocalerror: local variable 'u' referenced before assignment

user_a = "no selection" def if_statement():     user_choice = input("pick 1 or 2\n")     if user_choice == "1":         user_a = input("what equal?\n")         if_statement()     elif user_choice == "2":         print("a equals: " + user_a)         if_statement() if_statement() 

can me on this? must specify new python. thank in advance.

solution(s):

use default values parameters:

def if_statement(user_a='no selection'):     user_choice = raw_input("pick 1 or 2\n")     if user_choice == "1":         u = input("what equal?\n")         if_statement(user_a=u)     elif user_choice == "2":         print("a equals: " + user_a)          if_statement(user_a=user_a)  if_statement() 

or, can use global this:

user_a = "no selection" def if_statement():     global user_a # here trick ;-)     user_choice = raw_input("pick 1 or 2\n")     if user_choice == "1":         user_a = input("what equal?\n")         if_statement()     elif user_choice == "2":         print("a equals: " + user_a)         if_statement()  if_statement()