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Note: If the reader hasn’t learned about functions defined with def, please refer to here first

Definition Syntax

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<function_name> = lambda <parameters>: <return_value>

Equivalent to:

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def <function_name>(<parameters>):
    return <return_value>

Can also be defined as anonymous function (nameless function):

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lambda <parameters>: <return_value>

We can confirm that lambda function objects have the same type (function) as those defined with def:

Invocation

For anonymous functions, the invocation form is:

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(lambda <parameters>: <return_value>)(<arguments>)

For named functions:

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<function_name>(<arguments>)

Function to calculate $a+b$:
a+b_img

No Return Value

lambda functions can also have no return value.
Example:

Lambda functions without return value are generally used for performing actions, such as print('Hello World') etc.