def get_campus(text):
    """
    Check which campus is mentioned in the given text.

    A campus can be denoted by its full name or by its three-letter acronym.

    Args:
        text: The text in which the occurrence of the campuses is checked.

    Returns:
        A list with acronyms for all UAntwerp campuses that were mentioned in the text. Defaults to CMI if no campus is
        explicitly mentioned.
    """
    campus_options = [('cde', ['cde', 'drie eiken']), ('cgb', ['cgb', 'groenenborger']),
                      ('cmi', ['cmi', 'middelheim']), ('cst', ['cst', 'stad', 'city'])]

    campus = sorted([c_code for c_code, c_texts in campus_options if any(c_text in text for c_text in c_texts)])
    return campus if len(campus) > 0 else ['cmi']