[Tut] Python callable() Function

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Python callable() Function



Python’s built-in

Code:

callable(object)

returns

Code:

True

if you could call the

Code:

object

argument like a function with the trailing parentheses in

Code:

object()

. You can make any object callable by implementing the instance’s

Code:

__call__()

method. For example,

Code:

callable(callable)

returns

Code:

True

because

Code:

callable

is a function object. But

Code:

callable(3)

returns

Code:

False

because an integer is not a function you can call.

Here’s a minimal example:

Code:

>>> callable(callable) True >>> callable(3) False

Note: The function

Code:

callable()

was first removed in Python 3.0 but then reintroduced in version 3.2 and above.

Code:

Syntax: callable(object)

Argument |

Code:

object

|
Any Python object such as a custom object, a list, a function, a class, or any other object.

Return Value |

Code:

Boolean: True/False

|
Returns

Code:

True

if the object can be called with object()
Returns

Code:

False

otherwise.

Here are some basic usages of the function:

Code:

Input : callable(42) Output : False Input : callable(int) Output : True Input : callable(callable) Output : True

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How to Check Whether a Function Object is Callable

The following code shows you how to use the callable() method to check whether an arbitrary object is a function, method, or another callable object:

Code:

def finxter(): return 'Python' print(callable(finxter)) # True f = finxter print(callable(f)) # True print(callable(finxter())) # False

How to Create Your Own Callable Object

The following code shows you how to create your own callable object.

Code:

class Car: def __call__(self): print('brumm') porsche = Car() # Is it callable? print(callable(porsche)) # True # Call it! porsche() # brumm

This is an interesting way to make any instance instantly callable so that it can be used as a function.

Summary

Python’s built-in

Code:

callable(object)

returns

Code:

True

if you can call the

Code:

object

argument like a function with the trailing parentheses in

Code:

object()

.

Otherwise, it returns

Code:

False

.

For example,

Code:

callable(callable)

returns

Code:

True

because

Code:

callable

is a function object. But

Code:

callable(3)

returns

Code:

False

because an integer is not a function you can call.

You can make any object callable by implementing the instance’s

Code:

__call__()

method.

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