How to Remove Duplicates From a Python List
Learn how to remove duplicates from a List in Python.
Example
Remove any duplicates from a List:
mylist = ["a", "b", "a", "c", "c"]
mylist = list(dict.fromkeys(mylist))
print(mylist)
Run example »
Example Explained
First we have a List that contains duplicates:
A List with Duplicates
mylist = ["a", "b", "a", "c", "c"]
mylist = list(dict.fromkeys(mylist))
print(mylist)
Create a dictionary, using the List items as keys. This will automatically remove any duplicates because dictionaries cannot have duplicate keys.
Create a Dictionary
mylist = ["a", "b", "a", "c", "c"]
mylist = list(dict.fromkeys(mylist))
print(mylist)
Then, convert the dictionary back into a list:
Convert Into a List
mylist = ["a", "b", "a", "c", "c"]
mylist = list(dict.fromkeys(mylist))
print(mylist)
Now we have a List without any duplicates, and it has the same order as the original List.
Print the List to demonstrate the result
Print the List
mylist = ["a", "b", "a", "c", "c"]
mylist = list(dict.fromkeys(mylist))
print(mylist)
Create a Function
If you like to have a function where you can send your lists, and get them back without duplicates, you can create a function and insert the code from the example above.
Example
def my_function(x):
return list(dict.fromkeys(x))
mylist =
my_function(["a", "b", "a", "c", "c"])
print(mylist)
Run example »
Example Explained
Create a function that takes a List as an argument.
Create a Function
def my_function(x):
return list(dict.fromkeys(x))
mylist =
my_function(["a", "b", "a", "c", "c"])
print(mylist)
Create a dictionary, using this List items as keys.
Create a Dictionary
def my_function(x):
return list(dict.fromkeys(x))
mylist =
my_function(["a", "b", "a", "c", "c"])
print(mylist)
Convert the dictionary into a list.
Convert Into a List
def my_function(x):
return list(dict.fromkeys(x))
mylist =
my_function(["a", "b", "a", "c", "c"])
print(mylist)
Return the list
Return List
def my_function(x):
return list(dict.fromkeys(x))
mylist =
my_function(["a", "b", "a", "c", "c"])
print(mylist)
Call the function, with a list as a parameter:
Call the Function
def my_function(x):
return list(dict.fromkeys(x))
mylist = my_function(["a", "b", "a", "c", "c"])
print(mylist)
Print the result:
Print the Result
def my_function(x):
return list(dict.fromkeys(x))
mylist = my_function(["a", "b", "a", "c", "c"])
print(mylist)
