Fix Python – What is the difference between shallow copy, deepcopy and normal assignment operation?

import copy

a = “deepak”
b = 1, 2, 3, 4
c = [1, 2, 3, 4]
d = {1: 10, 2: 20, 3: 30}

a1 = copy.copy(a)
b1 = copy.copy(b)
c1 = copy.copy(c)
d1 = copy.copy(d)

print(“immutable – id(a)==id(a1)”, id(a) == id(a1))
print(“immutable – id(b)==id(b1)”, id(b) == id(b1))
print(“mutable – id(c)==id(c1)”, id(c) == id(c1))
print(“mutable – id(d)==id(d1)”, id(….

Fix Python – Is it possible only to declare a variable without assigning any value in Python?

Is it possible to declare a variable in Python, like so?:
var

so that it initialized to None? It seems like Python allows this, but as soon as you access it, it crashes. Is this possible? If not, why?
EDIT: I want to do this for cases like this:
value

for index in sequence:

if value == None and conditionMet:
value = index
break….