Assigning empty value or string in Python

I would like to understand if there is a difference between assigning an empty value and an empty output, as follows:

1> Assigning a value like this

string = ""

2> An empty value returned as output

string = "abcd:"
str1, str2 = split(':')

In other words, is there a difference in values of 'string' in 1> and 'str2' in 2>? And how would a method see the value of 'str2' if it is passed as an argument?

---

Checking equality with ==

>>> string = ""
>>> s = "abcd:"
>>> str1, str2 = s.split(':')
>>> str1
'abcd'
>>> str2
''
>>> str2 == string
True

Maybe you were trying to compare with is . This is for testing identity: a is b is equivalent to id(a) == id(b) .

Or check both strings for emptiness:

>>> not str2
True
>>> not string
True
>>> 

So that both are empty ...

---

If you will check id(string) in case-1 and id(str2) in case2, it will give u the same value, both the string objects are same.

def mine(str1, str2):
    print str1, str2

see the above method you can call mine(* string.split(':')) it will pass the 'abcd:' as str1 = 'abcd' and str2 = ''.

---

In other words, is there a difference in values of 'string' in 1> and 'str2' in 2>?

No, there is no difference, both are empty strings "" .

And how would a method see the value of 'str2' if it is passed as an argument?

The method would see it as a string of length 0, in other words, an empty string.

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