def linebreaker(l, break_pt=16):
    """
    used for adding labels in plots.

    :param l: list of strings
    :param break_pt: number, insert new line after this many letters 
    """
    l_out = []
    for i in l:
        if len(i) > break_pt:
            i_words = i.split(' ')
            i_out = ''
            line_len = 0
            for w in i_words:
                line_len += len(w) + 1
                if i_words.index(w) == 0:
                    i_out = w
                elif line_len > break_pt:
                    line_len = 0
                    i_out = '%s\n%s' % (i_out, w)
                else:
                    i_out = '%s %s' % (i_out, w)
            l_out.append(i_out)
        else:
            l_out.append(i)
    return l_out
