def make_set(str_data, name=None):
    """
    Construct a set containing the specified character strings.

    Parameters
    ----------
    str_data : None, str, or list of strs
        Character string(s) to be included in the set.

    name : str, optional
        A name to be used in error messages.

    Returns
    -------
    set
        A set of character strings.
    """
    if not str_data:
        return set()
    elif isinstance(str_data, str):
        return {str_data}
    elif isinstance(str_data, set):
        return str_data
    elif isinstance(str_data, list):
        return set(str_data)
    elif name:
        raise TypeError("The {} argument should be str, set, or list: {}".format(name, str_data))
    else:
        raise TypeError("The argument should be str, set, or list: {}".format(str_data))