def METHOD_NAME(prefix: str) -> str:
    """
    Normalizes a DDC prefix to be used in searching. Integer prefixes are not modified
    >>> normalize_ddc_prefix('1')
    '1'
    >>> normalize_ddc_prefix('1.1')
    '001.1'
    """
    # 23.* should become 023*
    # 23.45* should become 023.45*
    if '.' in prefix:
        normed = normalize_ddc(prefix)
        return normed[0] if normed else prefix
    # 0* should stay as is
    # 23* should stay as is
    # j* should stay as is
    else:
        return prefix