Python Lambda expression: write code like poetry

Lambda expressions are a powerful feature in python that allow you to create anonymous functions. An anonymous function is a function without a name that can be passed as a parameter to other functions.

The syntax of Lambda expression is very simple. It consists of the keyword lambda followed by a parameter list and an expression. For example, the following lambda expression calculates the sum of two numbers:

lambda x, y: x + y

This lambda expression can be passed to other functions as parameters. For example, the following code uses a lambda expression as a parameter to increment each element in the list by 1:

numbers = [1, 2, 3, 4, 5]
result = map(lambda x: x + 1, numbers)
print(list(result))

Output:

[2, 3, 4, 5, 6]

Lambda expressions can make code more concise and easier to read. For example, the following code uses a lambda expression to convert a list of strings to a list of integers:

strings = ["1", "2", "3", "4", "5"]
numbers = list(map(lambda x: int(x), strings))
print(numbers)

Output:

[1, 2, 3, 4, 5]

Lambda expressions can also be used to create more advanced functions. For example, the following code uses a lambda expression to create a function that returns a function that calculates the sum of two numbers:

def make_adder(x):
return lambda y: x + y

We can use the make_adder() function to create new functions that can add different numbers to a given number. For example, the following code uses the make_adder() function to create two functions that add 1 and 2 to a given number respectively:

adder1 = make_adder(1)
adder2 = make_adder(2)

We can add different numbers to the given number using the adder1() and adder2() functions. For example, the following code uses the adder1() function to add 1 to the number 3, and uses the adder2() function to add 2 to the number 3:

print(adder1(3))
print(adder2(3))

Output:

4
5

Lambda expressions are a very powerful tool that can make Python code more concise and easier to read. If you want to write Python code that is more efficient and easier to maintain, then you should learn how to use lambda expressions.

In addition to the above examples, lambda expressions can also be used for the following purposes:

• As a callback function for thread or process
• As a decorator
• As a generator
• As a closure

In short, lambda expressions are a very useful feature in Python that can make your code more concise, easier to read and maintain. If you want to become a good Pythonprogrammer, then you should learn how to use lambda expressions.

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