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# Python Lambda

A lambda function is a small anonymous function.

A lambda function can take any number of arguments, but can only have one expression.

## Syntax

lambda arguments : expression

The expression is executed and the result is returned:

### Example

Add 10 to argument `a`, and return the result:

x = lambda a : a + 10
print(x(5))
Try it Yourself »

Lambda functions can take any number of arguments:

### Example

Multiply argument `a` with argument `b` and return the result:

x = lambda a, b : a * b
print(x(5, 6))
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### Example

Summarize argument `a`, `b`, and `c` and return the result:

x = lambda a, b, c : a + b + c
print(x(5, 6, 2))
Try it Yourself »

## Why Use Lambda Functions?

The power of lambda is better shown when you use them as an anonymous function inside another function.

Say you have a function definition that takes one argument, and that argument will be multiplied with an unknown number:

def myfunc(n):
return lambda a : a * n

Use that function definition to make a function that always doubles the number you send in:

### Example

def myfunc(n):
return lambda a : a * n

mydoubler = myfunc(2)

print(mydoubler(11))
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Or, use the same function definition to make a function that always triples the number you send in:

### Example

def myfunc(n):
return lambda a : a * n

mytripler = myfunc(3)

print(mytripler(11))
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Or, use the same function definition to make both functions, in the same program:

### Example

def myfunc(n):
return lambda a : a * n

mydoubler = myfunc(2)
mytripler = myfunc(3)

print(mydoubler(11))
print(mytripler(11))
Try it Yourself »

Use lambda functions when an anonymous function is required for a short period of time.

## Exercise:

Create a lambda function that takes one parameter (`a`) and returns it.

```x =
```

Start the Exercise