def make_relative_path(source, dest, dest_is_directory=True):
    source = os.path.dirname(source)
    if not dest_is_directory:
        dest_filename = os.path.basename(dest)
        dest = os.path.dirname(dest)
    dest = os.path.normpath(os.path.abspath(dest))
    source = os.path.normpath(os.path.abspath(source))
    dest_parts = dest.strip(os.path.sep).split(os.path.sep)
    source_parts = source.strip(os.path.sep).split(os.path.sep)
    while dest_parts and source_parts and dest_parts[0] == source_parts[0]:
        dest_parts.pop(0)
        source_parts.pop(0)
    full_parts = ['..']*len(source_parts) + dest_parts
    if not dest_is_directory:
        full_parts.append(dest_filename)
    if not full_parts:
        # Special case for the current directory (otherwise it'd be '')
        return './'
    return os.path.sep.join(full_parts)



############################################################
## Bootstrap script creation:
fetch artefacts
dataset/ETHPy150Open femmerling/backyard/virtualenv.py/make_relative_path--crossover with--dataset/ETHPy150Open projectatomic/atomic-reactor/atomic_reactor/plugins/pre_pyrpkg_fetch_artefacts.py/DistgitFetchArtefactsPlugin.run