def METHOD_NAME(dockerfile_content: str, version: str) -> str:
    """Replace Renku version in the Dockerfile."""
    return re.sub(
        r"^\s*ARG RENKU_VERSION=(\d+\.\d+\.\d+\S*)$",
        f"ARG RENKU_VERSION={version}",
        dockerfile_content,
        flags=re.MULTILINE,
    )