Describe functions in Python
Python Functions : A function is a block of organized, reusable code that is used to perform a single, related action. Python gives us many built-in functions like print(), etc. but you can also create your own functions. These functions are called user-defined functions. Parameter Passing : We can pass arguments to a function either by value or by reference. Call by Value : Sometimes it's also called pass by value. In call-by-value, the argument expression is evaluated, and the result of this evaluation is bound to the corresponding variable in the function. So, if the expression is a variable, a local copy of its value will be used, i.e. the variable in the caller's scope will be unchanged when the function returns. Call by Reference : It is also known as pass-by-reference. In this a function gets an implicit reference to the argument, rather than a copy of its value. As a consequence, the function can modify the argument, i.e. the value of the variable in