Writing PNG with pure Python

[Johann C. Rocholl]

How about this here construct?

#!/usr/bin/env python
# png.py - PNG encoder in pure Python
# Copyright (C) 2006 Johann C. Rocholl <johann at browsershots.org>
#
# This file is licensed alternatively under one of the following:
# 1. GNU Lesser General Public License (LGPL), Version 2.1 or newer
# 2. GNU General Public License (GPL), Version 2 or newer
# 3. Apache License, Version 2.0 or newer
# 4. The following license (aka MIT License)
#
# --------------------- start of license -----------------------------
# Copyright (C) 2006 Johann C. Rocholl <johann at browsershots.org>
#
# Permission is hereby granted, free of charge, to any person
# obtaining a copy of this software and associated documentation files
# (the "Software"), to deal in the Software without restriction,
# including without limitation the rights to use, copy, modify, merge,
# publish, distribute, sublicense, and/or sell copies of the Software,
# and to permit persons to whom the Software is furnished to do so,
# subject to the following conditions:
#
# The above copyright notice and this permission notice shall be
# included in all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
# BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
# ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
# CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
# SOFTWARE.
# ----------------------- end of license -----------------------------
#
# You may not use this file except in compliance with at least one of
# the above four licenses.