map () function

map () is a function of higher order the python, python higher order function refers to a function can be a function of the functional programming of such parameters refers to a highly abstract programming paradigm.

To understand higher-order functions, we must first clear function can be assigned to a variable, the function name itself is a variable, you can assign it to other values, not just from the variable names, function names and prevent conflict.

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map () function is a special place in its first parameter is a variable to a function of the second parameter is a sequence, usually list, each element of the list would enter the function, the return value of each finally merged into a new list is returned.