TypeError: 'list' object is not callable - python [solved]

What does list object is not callable mean ?

"List object is not callable" is one of the most common errors in python. It means that you are attempting to call a list ( a non callable object ) like a function.
In simple words, it basically means that you are trying to call a function which has a name of a list, in your code. Let us understand this with an example.

Example

bugz = [1,2,3] # a list object

bugz() # calling a function which has the name of a list 

Output

TypeError: 'list' object is not callable

In the above example, the integer list bugz is being called like a function ( i.e. by adding parentheses () ), resulting in the above mentioned typeerror.

This unintentionally happens mostly in two situations, they are :

• When a built-in function with the same name as your list exists.

• When you attempt to access elements of the list by using parentheses rather than square brackets.

Built-in name being used as a variable name

Regardless of the scope of the code, the Python interpreter provides more than 70 built-in functions and types ( that have predefined values ) which are always accessible. Python doesn't stop users from reassigning the built-in names, which means that all the built-in names can be used as the names of variables.

If you name a list object the same as a built-in function, the next time when you attempt to call the built-in function, python assumes that you are referring to the list object and not the built-in function.

Let us understand this with an example :

Example

list = [1,2,3] # naming the list object "list"
      
# built-in list function being overrided as a list object

list2 = list("bugz") # referring to the list object as a function

print(list,list2)

Output

TypeError: 'list' object is not callable

In the above example, the list object is being named as "list" ( same as a built-in function ), which results in the existing list function being overrided as a list object.

This means that Python now considers the list name to be referring to a list object rather than a function. Therefore, when the built-in list function is called in the next line, python assumes that you are calling the list object, and as you cannot call a non callable object ( list ) like a function, this typeerror occurs.

How to fix list object is not callable : variable name being same as the built-in name ?

The solution for this typeerror is very simple. It is to update the name of the list object such that it differs from the names of the python built-in functions.

Example

list1 = [1,2,3] # changing the list name to "list1"

# list function not being overrided

list2 = list("bugz") # calling the built-in list function

print(list1,list2)

Output

[1, 2, 3] ['b', 'u', 'g', 'z']

In the above example, the name of the list instance is being changed to list1. Therefore, the built-in list function is not being overrided. Hence, it is very much recommended to not use built-in names of python ( such as list, map, range, etc. ) as variables.

Using parentheses instead of square brackets to access elements of a list.

While working with lists, accessing elements of lists is a common thing. In python, this can be done by specifying the index of the elements and the name of the list. For example; bugz[3] will return the element with the index number 3 from the list named bugz.

Usually people tend to use parentheses () instead of square brackets [] which results in the typeerror mentioned above.

Example

bugz = ["zero","one","two"]

# using bugz() 👇 instead of bugz[] 

print(bugz(1))

Output

TypeError: 'list' object is not callable

In the above example, to access the element with index 1 from the list bugz, parentheses () are being used instead of square brackets [].

This makes python interpret it as a function call, and as bugz is a list ( a non callable object ) and you cannot call a list like a function, the error mentioned above occurs.

How to fix list object is not callable : parentheses being used instead of square brackets ?

The simplest solution for this error is to access the elements from the list in the correct way, i.e. by using square brackets [] instead of parentheses (). Let us understand this with an example.

Example

bugz = ["zero","one","two"]

print(bugz[0])
print(bugz[1])
print(bugz[2])

Output

zero
one
two

In the above example, the use of parentheses () to access elements from the list is avoided.

Conclusion

TypeError: 'list' object is not callable error usually occurs when parentheses () are placed just after the name of a list. For example; list_name() results in the above mentioned TypeError. Try using advanced IDEs which help you in avoiding these type of errors.