To call a built-in function, you need to use parentheses. Parentheses distinguish function calls from other operations that can be performed on some objects, like indexing.
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If you try to use square brackets to call a built-in function, you\u2019ll encounter the \u201cTypeError: \u2018builtin_function_or_method\u2019 object is not subscriptable\u201d error.
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In this guide, we talk about what this error means and why you may encounter it. We\u2019ll walk through an example so that you can figure out how to solve the error.<\/p>\n\n\n\n
Only iterable objects are subscriptable. Examples of iterable objects include lists<\/a>, strings<\/a>, and dictionaries. Individual values in these objects can be accessed using indexing. This is because items within an iterable object have index values<\/a>. Consider the following code:<\/p>\n\n\n\n Our code returns \u201cEnglish\u201d. Our code retrieves the first item in our list, which is the item at index position 0. Our list is subscriptable so we can access it using square brackets. Built-in functions are not subscriptable. This is because they do not return a list of objects that can be accessed using indexing. The \u201cTypeError: \u2018builtin_function_or_method\u2019 object is not subscriptable\u201d error occurs when you try to access a built-in function using square brackets. This is because when the Python interpreter sees square brackets it tries to access items from a value as if that value is iterable.<\/p>\n\n\n\n We\u2019re going to build a program that appends all of the records from a list of homeware goods to another list. An item should only be added to the next list if that item is in stock. Start by defining a list of homeware goods and a list to store those that are in stock:<\/p>\n\n\n\n The \u201cin_stock\u201d list is presently empty. This is because we have not yet calculated which items in stock should be added to the list. Next, we use a for loop<\/a> to find items in the \u201chomewares\u201d list that are in stock. We\u2019ll add those items to the \u201cin_stock\u201d list:<\/p>\n\n\n\n We use the append() method<\/a> to add a record to the \u201cin_stock\u201d list if that item is in stock. Otherwise, our program does not add a record to the \u201cin_stock\u201d list. Our program then prints out all of the objects in the \u201cin_stock\u201d list. Let\u2019s run our code and see what happens:<\/p>\n\n\n\n Our code returns an error.<\/p>\n\n\n\n Take a look at the line of code that Python points to in the error: We\u2019ve tried to use indexing syntax to add an item to our \u201cin_stock\u201d list variable<\/a>. This is incorrect because functions are not iterable objects. To call a function, we need to use parenthesis. We fix this problem by replacing the square brackets with parentheses: Let\u2019s run our code:<\/p>\n\n\n\n Our code successfully calculates the items in stock. Those items are added to the \u201cin_stock\u201d list which is printed to the console.<\/p>\n\n\n\n
<\/p>\n\n\n\nlanguages = ["English", "French"]\nprint(languages[0])<\/pre><\/div>\n\n\n\n
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<\/p>\n\n\n\nAn Example Scenario<\/h2>\n\n\n\n
<\/p>\n\n\n\nhomewares = [\n\t{ "name": "Gray Lampshade", "in_stock": True },\n\t{ "name": "Black Wardrobe", "in_stock": True },\n{ "name": "Black Bedside Cabinet", "in_stock": False }\n]\nin_stock = []<\/pre><\/div>\n\n\n\n
<\/p>\n\n\n\nfor h in homewares:\n\tif h["in_stock"] == True:\n\t\tin_stock.append[h]\n\nprint(in_stock)<\/pre><\/div>\n\n\n\n
<\/p>\n\n\n\nTraceback (most recent call last):\n File "main.py", line 10, in <module>\n\tin_stock.append[h]\nTypeError: 'builtin_function_or_method' object is not subscriptable<\/pre><\/div>\n\n\n\n
The Solution<\/h2>\n\n\n\n
<\/p>\n\n\n\n\tin_stock.append[h]<\/pre><\/div>\n\n\n\n
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<\/p>\n\n\n\n\tin_stock.append(h)<\/pre><\/div>\n\n\n\n
[{'name': 'Gray Lampshade', 'in_stock': True}, {'name': 'Black Wardrobe', 'in_stock': True}]<\/pre><\/div>\n\n\n\n