Head First Python--module: nester.py

"""This is the "nester.py" module, and it provides one function called print_lol()
which prints lists that may or may not include nested lists."""

import sys

def print_lol(the_list, indent=False, level=0, fh=sys.stdout):
    """This function takes a positional argument called "the_list", which is any
    Python list (of, possibly, nested lists). Each data item in the provided list
    is (recursively) printed to the screen on its own line."""

    for each_item in the_list:
        if isinstance(each_item, list):
            print_lol(each_item, indent, level+1, fh)
        else:
            if indent:
                for tab_stop in range(level):
                    print('\t', end = '', file = fh)
            print(each_item, file=fh)