Assign Function to a Variable in Python

In Python, functions are first-class objects, meaning they can be assigned to variables, passed as arguments and returned from other functions. Assigning a function to a variable enables function calls using the variable name, enhancing reusability.

Example:

# defining a function def a(): print("GFG") # assigning function to a variable var=a # calling the variable var() 

GFG 

Explanation: a() prints "GFG". It is assigned to var, which now holds a reference to a(). Calling var() executes a().

Implementation:

To assign a function to a variable, use the function name without parentheses (). If parentheses are used, the function executes immediately and assigns its return value to the variable instead of the function itself.

Syntax:

# Defining a function

def fun():

# Function body

pass

# Assigning function to a variable

var = fun

# Calling the function using the variable

var()

Example 1: Function with Local and Global Variables

x = 123 # global variable def display(): x = 98 # local variable print(x) print(globals()['x']) # accesses global x print(x) a = display # assign function to a variable a() # call function a() # call function 

123 98 123 98 123 

Explanation: Inside display(), local x = 98 is printed first, then global x = 123 using globals()['x']. The function is assigned to a, allowing display() to run twice via a().

Example 2: Assigning a Function with Parameters

# defining a function def fun(num): if num % 2 == 0: print("Even number") else: print("Odd number") # assigning function to a variable a = fun # calling function using the variable a(67) a(10) a(7) 

Odd number Even number Odd number 

Explanation: fun(num) checks if num is even or odd and prints the result. It is assigned to a, allowing it to be called using a(num), which executes fun(num).

Example 3: Assigning a Function that Returns a Value

# defining a function def fun(num): return num * 40 # assigning function to a variable a = fun # calling function using the variable print(a(6)) print(a(10)) print(a(100)) 

240 400 4000 

Explanation: function fun(num) returns num * 40. It is assigned to a, allowing a(num) to execute fun(num).