import re


def _find_special_id(txt: str, pattern: str, split_str: str) -> list:
    """Creates an accession ID from starting characters in `pattern` and
    digits following `split_str` in `txt`.

    Args:
        txt (str): Text to search for ID
        pattern (str): Pattern containing at the start the character prefix and
                       at the end the remaining digits of the accession ID
        split_str (str): String separating the digit part of the ID

    Returns:
        list: List with accession ID.
    """
    match = re.findall(f'({pattern})', txt)
    ids = []
    if len(match) != 0:
        for match in match:
            split_match = match.split(split_str)
            prefix = re.findall("[A-Z]+", split_match[0])[0]
            number = split_match[-1].strip()
            ids += [prefix + number]
    return ids