def serialize_all(
    nodes,
    stream=None,
    Dumper=Dumper,
    canonical=None,
    indent=None,
    width=None,
    allow_unicode=None,
    line_break=None,
    encoding=None,
    explicit_start=None,
    explicit_end=None,
    version=None,
    tags=None
):
    """
    Serialize a sequence of representation trees into a YAML stream.
    If stream is None, return the produced string instead.
    """
    getvalue = None
    if stream is None:
        if encoding is None:
            stream = io.StringIO()
        else:
            stream = io.BytesIO()
        getvalue = stream.getvalue
    dumper = Dumper(
        stream,
        canonical=canonical,
        indent=indent,
        width=width,
        allow_unicode=allow_unicode,
        line_break=line_break,
        encoding=encoding,
        version=version,
        tags=tags,
        explicit_start=explicit_start,
        explicit_end=explicit_end
    )
    try:
        dumper.open()
        for node in nodes:
            dumper.serialize(node)
        dumper.close()
    finally:
        dumper.dispose()
    if getvalue:
        return getvalue()

    Serialize a sequence of representation trees into a YAML stream.
    If stream is None, return the produced string instead.
    
metadrive/render_pipeline/rplibs/yaml/yaml_py3/__init__.py