A function is a block of code which helps to break our program into smaller chunks or sub-programs, making it more organized and easily understandable. It runs as and when called and also helps to increase the code reusability.

Create a function

def function_name():
       print("Function created")

function_name()

Here,

def is the keyword used to define a function
: is used to mark the end of function header
print statement is the function body
function_name() is a way of calling the created function

Built-in functions

These are the predefined functions already available in python and can be used directly when required. The following are some built-in functions with their examples.

Input function

It enables us to take user input as a string until it encounters a newline without evaluating its value.

The use of int and float in the statement can enable us to accept an integer and floating point number as well.

Eval function

It is used to evaluate the values of a string.

The value returned by a function may be used as an argument for another function in a nested manner. This is called Composition.

Print function

It is used to display the output provided as an argument on its execution. Here, name is the function's argument.

In order to display multiple values in a single print statement, we separate the values using commas (,). These values will be displayed in the same line. To display the values in separate lines using a single print statement, we make use of escape sequence such as \n i.e. newline character.

Type function

It is used to determine the data type of a value.

Round function

It is used to round up a number upto a specified number of decimal places. The first argument specifies the value to be rounded and the second specifies the number of decimal digits desired after rounding up. If the second argument is missing, then the number is rounded up to an integer.

Max and min functions

They are used to find the maximum and minimum values respectively out of the several values. The operands must be compatible for comparison. The integer and floating point values are compatible for comparison. These functions can also operate on string values.