Passing Lists between Functions-CodePudding

Background - I have created 2 functions as part of a project to make API calls using values from an entities_list and views_list. The first function def user_inputs() asks for 2 user inputs as integer values (with v.basic error handling). The second function def url_constructor() iterates through the values in the 2x lists (using nested loops) and constructs URLs for my API call, before saving the URLs in the url_list, before a latter function will handle the API calls.

My issue - I am having issues accessing entities_list and views_list, specifically returning the lists from my def user_inputs() and having as arguments in the def url_constructor()

My code - you can see from this function, that I have attempted to return both lists respectively. Nothing breaks, and I can input my values into the list without issue -

def user_inputs():
    while True:
        try:
            entities_list = [int(x) for x in input("Entities for API Call:\n").split(', ')]
        except ValueError:
            print("---ERROR: MUST BE COMMA SEPERATED VALUES---")
            return entities_list
            continue
        break
    while True:
        try:
            views_list = [int(x) for x in input("Views for API Call:\n").split(', ')]
        except ValueError:
            print("---ERROR: MUST BE COMMA SEPERATED VALUES---")
            return views_list
            continue
        break
    return entities_list, views_list
user_inputs()

However, we running the following code block for my def user_inputs(), I get a NameError: name 'entities_list' is not defined -

def url_constructor(entities_list, views_list):
    str = 'https://some_url/{}/view{}'
    for entity in entities_list:
        for view in views_list:
            url = str.format(entity, view)
            url_list.append(ur)
url_constructor(entities_list, views_list)

I am not looking for someone to do my work for me, however just guide me in the right direction. Your help is greatly appreciated!

CodePudding user response：

Look at the example below and try to apply to your code

def foo():
  list_a = [5]
  list_b = [12]
  return list_a,list_b

def bar(lst):
  print(lst)

a,b = foo()
bar(a)

CodePudding user response：

I think you need:

entities_list, views_list = user_inputs()

otherwise, the values returned from the user_inputs function get thrown away because they aren't assigned to anything.

Protip: you could also do:

url_constructor(*user_inputs())

https://docs.python.org/3/tutorial/controlflow.html#unpacking-argument-lists