How the scoping works in python?

Question

I am new to object oriented world and trying following code in python and calling function of one class from another class.

Mycode.py

class A:

def funcA():
    return "sometext"

def funcB(self):
    self.funcA()  # calls func A internally from funcB

secondcode.py

from Mycode import A

class B:
      def funcC(self):
          A.funcB(self)  # it gives error for call funcA() as it is unknown to class B
if __name__ == '__main__':

b=B()
b.funcC()

AttributeError: 'B' object has no attribute 'funcA' How does scoping work with respect to classes in python?

Could you fix the indentation here so that it's identical to the files on your computer? — Patrick Haugh, Oct 23 '18 at 14:35
Hi, welcome to Python. Indention is very important in Python. Please make sure your indention is correct before submitting your question. — Sraw, Oct 23 '18 at 14:35
Also I believe there is an error in `def func C(self): ` line. Please fix it so that your code is syntatically correct and well indented. — running.t, Oct 23 '18 at 14:37

score 0 · Answer 1 · answered Oct 23 '18 at 14:38

0

The problem is not scope, but you have misunderstanding on self.

class B:
      def func C(self):
          A.funcB(self)

In the above code, self is an instance of B instead of A. But A.funcB should accept an instance of A. Or self.funcA in A.funcB is unavaliable.

answered Oct 23 '18 at 14:38

Sraw

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I think the problem is about understanding of [bound and unbound functions in python](https://stackoverflow.com/questions/114214/class-method-differences-in-python-bound-unbound-and-static) – running.t Oct 23 '18 at 14:40
I am new can someone fix the issue here so that i can call funcB from using A.funcB which should call internally funcA internally? – Manish Oct 23 '18 at 14:42
@running.t I somehow disagree. Because many new comers think that `self` is a key word or let's say magic word like `this` in Java. But actually it isn't. It is just a normal variable. It can be whatever you want. It can be `def funcC(hahah):`. And if you use `hahah` as `self`, it can still work. – Sraw Oct 23 '18 at 14:42
Still i could not understand. Pls help me in fixing my code. – Manish Oct 23 '18 at 14:48
@Manish It's hard to fix in this structure. Basically you need at least an instance of `A`. like `a = A() a.funcB()`. – Sraw Oct 23 '18 at 14:51

How the scoping works in python?

1 Answers1