Python - How To Check List Is Empty in Python

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This tutorial will introduce how to check if a list is empty in Python.

Use the if not Statement to Check if a List Is Empty or Not

In Python, if a list or some other data type is empty or NULL then it is considered False. The if not statement is used to execute a block of code if a condition is False; thus, we can use it to check if a list is empty or not. The following code will explain this.

lst = [] if not lst:     print("Empty") else:     print("Not Empty") 

Output:

Empty  

Use the len() Function to Check if a List Is Empty or Not

The len() function in Python returns the total number of elements in a list. So if the len() function returns 0 then the list is empty. We will implement this in the code below.

lst = [] if len(lst)==0:     print("Empty") else:     print("Not Empty") 

Output:

Empty 

Note that this method is considered a little slow but also works with a numpy array, whereas the if not method fails with numpy arrays.

Use an Empty List [] to Check if a List Is Empty or Not in Python

This is an unconventional method and is not used very frequently, but still, it is worth knowing and provides the same result. In this method, we directly compare our list to an empty list, and if the comparison returns True, then the list is empty. For example,

lst = [] if lst == []:     print("Empty") else:     print("Not Empty") 

Output:

Empty