Python - Membership Operators

Membership operators are used to check the membership of an element in a sequence like lists, tuple etc. Python supports two membership operators:

in - Returns true if a given element is present in the object.
not in - Returns true if a given element is not present in the object

Example: in operator

In the example below, the in operator is used to check the presence of given element in a sequence. It can also be used to print content of a sequence.

MyList = [10, 20, 30, 40]
MyTuple = ("Red", "Blue", "Green")

#checking if MyList contains 40
if 40 in MyList:
  print("MyList contains 40.")
else:
  print("MyList does not contain 40.")

#checking if MyTuple contains "White"
if "White" in MyTuple:
  print("MyTuple contains 'White'.")
else:
  print("MyTuple does not contain 'White'.")

#printing all content of MyList
print("MyList contains:", end=" ")
for i in MyList:
  print(i , end =" ")

The output of the above code will be:

MyList contains 40.
MyTuple does not contain 'White'.
MyList contains: 10 20 30 40

Example: not in operator

In the example below, the not in operator is used to check the presence of a given element in a given sequence.

MyList = [10, 20, 30, 40]
MyTuple = ("Red", "Blue", "Green")

#checking if MyList contains 40
if 40 not in MyList:
  print("MyList does not contain 40.")
else:
  print("MyList contain 40.")

#checking if MyTuple contains "White"
if "White" not in MyTuple:
  print("MyTuple does not contain 'White'.")
else:
  print("MyTuple contains 'White'.")

The output of the above code will be:

MyList contain 40.
MyTuple does not contain 'White'.

❮ Python - Operators