Python not equal operator

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In this post, we will see about Python not equal operator.

Not equal operator is denoted by != in Python and returns true when two variables are of same type but have different value. If two variable posses same value, then not equal operator will return False.


Python not equal operator example

Here is simple example of non equal operator

This will print True.

str1 = "world" str2 = "world" str3 = "WORLD" print(str1!=str2) print(str1!=str3)

Output:

False
True

str1!=str2 returns False:
As str1 and str2 are exactly same String, so it return False.

str1!=str3 returns True:
As str1 and str3 differ in case, it return True.

Please note that you can use <> for not equal in Python 2 but <> is deprecated in Python 3.


Python not equal operator in case of Custom object

When you call !=, python internally calls __ne__(self, other) method. In case of custom objects, you can implement your own version in the class.

Here is quick example.

class Country: name = '' population = 0 def __init__(self, name, population): self.name = name self.population = population def __ne__(self, other): # If different type, you can return true if type(other) != type(self): return True if self.name != other.name: return True else: return False india1 = Country('India', 1000) india2 = Country('India', 2000) china = Country('China', 3000) print(india1 != india2) print(india1 != china)

Output:

False
True

As you can see, we have implemented __ne__(self, other) and two countries are not equal, if there name are not same.

So that’s why
india1 != india2 returned False as name is same in both objects even though population is different.

That’s all about Python not equal operator.

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