def function_3(params: int, store_artifact=None):
    """An example of function that stores artifacts.

    Args:
        params: parameters for the function. Note that the name `params` is
          to follow the general conversion, but the function expects
          integer.
        store_artifact: callback for storing artifacts. See StoreArtifact
          protocol for explanation.

    Returns:
        The input argument multiplied by 2. As a side effect, binary
        representation of the input argument is stored as "bitstring"
        artifact.
    """
    bitstring = bin(params)[2:]
    if store_artifact:
        store_artifact("bitstring", bitstring)
    return 2 * params