Python word wrap function

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I'm working on creating function headers for our C development code. These headers include the function name, a purpose statement, input/output lists, etc. So my solution (because I'm lazy and prefer scripting to writing hundreds of lines of not-actually-code) is to write a Python script to write the headers. I put all the pertinent information (function names, variable names, descriptions, etc.) in an Excel spreadsheet and I'm using Python to read the data and properly format it. (See here and here for more info on using Python w/ Excel.) Things are going pretty well. The spreadsheet (and the script) are getting a little messy, but overall, it is faster (I think), more fun (definitely) and I believe will produce more consistent results. It also allows me to be more flexible if names or descriptions change in the future because I only need to change the information once in the spreadsheet instead of mutiple places in the actual .c files.

One of the rules for the function headers is that they must be 80 columns or less in width. It is annoying to wrap everything by hand so I wrote a Python function to do the wrapping. (I know Emacs could probably do all this in about 2 lines of Lisp, but I haven't learned that much yet.) Here is the script with a couple of examples:

def word_wrap(string, width=80, ind1=0, ind2=0, prefix=''):
    """ word wrapping function.
        string: the string to wrap
        width: the column number to wrap at
        prefix: prefix each line with this string (goes before any indentation)
        ind1: number of characters to indent the first line
        ind2: number of characters to indent the rest of the lines
    """
    string = prefix + ind1*" " + string
    newstring = ""
    if len(string) > width:
        while True:
            # find position of nearest whitespace char to the left of "width"
            marker = width-1
            while not string[marker].isspace():
                marker = marker - 1

            # remove line from original string and add it to the new string
            newline = string[0:marker] + "\n"
            newstring = newstring + newline
            string = prefix + ind2*" " + string[marker+1:]

            # break out of loop when finished
            if len(string) <= width:
                break
    
    return newstring + string

Example 1: wrap at 60 characters

string = "PURPOSE: To end world hunger, create peace for all people, solve all technological and scientific problems, make an exorbitant amount of money, and remain humble in the process."
print word_wrap(string, 60)

Results:

PURPOSE: To end world hunger, create peace for all people,
solve all technological and scientific problems, make an
exorbitant amount of money, and remain humble in the
process.

Example 2: wrap at 60 chars, with a prefix, and a hanging indent

print word_wrap(string, 60, 0, 9, " * ")

Results:

 * PURPOSE: To end world hunger, create peace for all
 *          people, solve all technological and scientific
 *          problems, make an exorbitant amount of money,
 *          and remain humble in the process.