How do I use the same variable in one function with another function, without making that variable Global?

How c开发者_如何学Pythonan I take one variable from one function and use it in another function without having to make that variable global?

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You have basically two choices.

One is to pass it to the second function as a parameter. (If you want the first function to see changes to the value, it needs to be a reference type (e.g. a dict/list) and you have to not overwrite the object, only modify it (e.g. a.append(b) rather than a = a + [b]).

The second is to define a class that can be used as a singleton. Technically, this is still defining something 'globally', but it lets you keep things grouped:

class FooSingleton(object):
    class_var = "foo"

def func1():
    FooSingleton.class_var = "bar"

def func2():
    print(FooSingleton.class_var)

(You could also do this with a dict instead of a class; matter of preference.)

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have the function take a parameter, and pass that parameter in.

def one_function():
  one_variable = ''
  return one_variable

def another_function(a_param):
  # do something to a_param
  return

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Technically possible and may be used, e.g. for memoisation (but then it is usually hidden behind a decorator and only implemented by people who are sure they do the right thing even though they might still feel a bit bad about it):

def g():
    if not hasattr(g, "x"):
        g.x = 0
    return g.x

g()
# 0

g.x = 100
g()
# 100

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You can use closure to handle this, or more natural is to define both functions as methods of a class and the "global" variable as member of the class.