''' Purpose: do some functions produces lists from a string
'''

def ints( ns ) :
    ''' Returns list of integers corresponding to the integer substrings in ns.
    '''
    # can't use int( ns ) because not correctly formatted for a single int
    numeric_strings = ns.split()  # gives us a list of numeric strings that were separated by space in ns

    result = []   # list of ints that's associated with the string ns
    # result can be our list accumulator

    # for each string in numeric strings
    for string in numeric_strings:
        # convert string into an int
        number = int( string )

        # put the new number into the list accumulator
        result.append( number )

    # now we have a list of ints instead of a list of numeric strings in our variable result
    return result
        
def parse_phone_string( pn ) :
    ''' Returns a three-element integer list for string phone # pn:
           1st element: pn area code
           2nd element: pn prefix
           3rd element: pn line number
    '''

    pass