human
Here's a good function header given the following:
I wrote the below code

    def indent(s, type=1):
        x = s.split('\n')
        r = ('+-%s\n' % x[0])
        for a in x[1:]:
            if (a == ''):
                continue
            if (type == 1):
                r += ('|    %s\n' % a)
            else:
                r += ('        %s\n' % a)
        return r
    if (len(subtrees) == 0):
        return ''
    f = ''
    for a in subtrees[:(-1)]:
        f += indent(a)
    f += indent(subtrees[(-1)], 2)
    return f

What's a good function header?
assistant
#Here's a good function header.

def pprint_nodes(subtrees):