@staticmethod
def _check_type(term):
    """Check type of input term, and return as a list.

        Parameters
        ----------
        term : str OR list of str
            New term to add to the object.

        Returns
        -------
        list of str
            New term, set as a list.
        """
    if isinstance(term, str):
        return [term]
    elif isinstance(term, list):
        return term
