<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def contribution_breakdown():
 """ Displays a table of the contributors and to what extent we have them to thank."""

    args = ['git', 'blame']
    counts = {}
    line_format = '{0:30}\t{1:>10}\t{2:>10}%'
    files = subprocess.check_output(['git', 'ls-files']).decode("utf-8").split('\n')

    for f in files[:-1]:
        if 'docs/latest' in f or '_themes' in f:
            continue  # skip generated stuff
        lines = subprocess.check_output(args + [f]).decode('utf-8')
        blames = [get_line_blame(line) for line in lines.split('\n')]
        for blame in blames:
            counts[blame] = counts.get(blame, 0) + 1

    total = sum([counts[count] for count in counts])
    contribs = [(user, counts[user]) for user in counts]
    contribs.sort(key=lambda x: x[1], reverse=True)

    print(line_format.format('User', 'Lines', 'Line '))

    for user in contribs:
        percent = floor(100.0 * user[1] / total)
        if percent == 0: percent = '>1'
        print(line_format.format(user[0], user[1], percent))

    print(line_format.format('Total', total, 100))