How to use the manubot.cite.csl_item.CSL_Item function in manubot

def citekey_to_csl_item(citekey, prune=True):
    """
    Generate a CSL Item (Python dictionary) for the input citekey.
    """
    from manubot.cite.csl_item import CSL_Item
    from manubot import __version__ as manubot_version

    citekey == standardize_citekey(citekey, warn_if_changed=True)
    source, identifier = citekey.split(":", 1)

    if source not in citeproc_retrievers:
        msg = f"Unsupported citation source {source!r} in {citekey!r}"
        raise ValueError(msg)
    citeproc_retriever = import_function(citeproc_retrievers[source])
    csl_item = citeproc_retriever(identifier)
    csl_item = CSL_Item(csl_item)

    note_text = f"This CSL JSON Item was automatically generated by Manubot v{manubot_version} using citation-by-identifier."
    note_dict = {"standard_id": citekey}
    csl_item.note_append_text(note_text)
    csl_item.note_append_dict(note_dict)

    short_citekey = shorten_citekey(citekey)
    csl_item.set_id(short_citekey)
    csl_item.clean(prune=prune)

    return csl_item

csl_items = []
    for path in paths:
        path = pathlib.Path(path)
        if not path.is_file():
            logging.warning(
                f"process.load_bibliographies is skipping a non-existent path: {path}"
            )
            continue
        for csl_item in load_bibliography(path):
            csl_item.note_append_text(
                f"This CSL JSON Item was loaded by Manubot v{manubot_version} from a manual reference file."
            )
            csl_item.note_append_dict({"manual_reference_filename": path.name})
            csl_items.append(csl_item)
    csl_items.extend(map(CSL_Item, extra_csl_items))
    manual_refs = dict()
    for csl_item in csl_items:
        try:
            csl_item.standardize_id()
        except Exception:
            csl_item_str = json.dumps(csl_item, indent=2)
            logging.info(
                f"Skipping csl_item where setting standard_id failed:\n{csl_item_str}",
                exc_info=True,
            )
            continue
        standard_id = csl_item["id"]
        csl_item.set_id(shorten_citekey(standard_id))
        csl_item.clean()
        manual_refs[standard_id] = csl_item
    return manual_refs

csl_items = []
    if use_pandoc_citeproc:
        from manubot.pandoc.bibliography import (
            load_bibliography as load_bibliography_pandoc,
        )

        csl_items = load_bibliography_pandoc(path)
    if not isinstance(csl_items, list):
        logging.error(
            f"process.load_bibliography: csl_items read from {path} are of type {type(csl_items)}. "
            "Setting csl_items to an empty list."
        )
        csl_items = []
    from manubot.cite.csl_item import CSL_Item

    csl_items = [CSL_Item(csl_item) for csl_item in csl_items]
    return csl_items

def assert_csl_item_type(x):
    if not isinstance(x, CSL_Item):
        raise TypeError(f"Expected CSL_Item object, got {type(x)}")