def is_supported_header(key):
    """Returns true if a standard supported header."""

    # Supported headers for object.
    supported_headers = [
        "cache-control",
        "content-encoding",
        "content-type",
        "content-disposition",
        "content-language",
        "x-amz-website-redirect-location",
        # Add more supported headers here.
    ]
    return key.lower() in supported_headers