Python utilities

Key information of the python strcutures are discussed here.

  1. global variable
    2. Example: 
x = "global"
def foo():
    global x
    y = "local"
    x = x * 2
    print(x)
    print(y)
    
foo()
  2. __init__ and __self__: __init__ does act like a constructor. You'll need to pass "self" to any class functions as the first argument if you want them to behave as non-static methods. "self" are instance variables for your class. 
    3. class MyClass(object):
    i = 123
    def __init__(self):
        self.i = 345

a = MyClass()
print(a.i)
print(MyClass.i)