abs
The abs function returns the absolute value of a number. The argument can be an integer or a real number. If it is a complex number, its modulus is returned.
Built-in
help
The help function invokes Python's built-in help system. If no argument is passed, the function returns a welcome message explaining the use of the function and inviting us to enter the search text. If the argument is a text string, that string is searched for as the name of a module, function, class, method, keyword, or topic in the documentation, and available help is displayed.
round
The round function rounds a number to a precision given by the number of decimal places specified as an argument. If the number of decimal places is not specified, 0 is taken as the default value.
The returned value is rounded to the nearest multiple of 10 ^ (- number of decimal places). If two multiples are equally close, the even value is taken.
