def telescopes_unicity(tel_list):
    """
    Check if all the telescopes in a list are unique
    Parameters
    ----------
    tel_list: list of telescopes classes

    Returns
    -------
    Boolean: True if all telescopes in the list are unique
    """
    are_unique = True
    for tel1 in tel_list:
        for tel2 in tel_list:
            if ((tel1.mirror_center == tel2.mirror_center).all() and tel1.id != tel2.id):
                print("Telescopes {0} and {1} are both at the same position {3}".format(tel1.id, tel2.id, tel1.mirror_center))
                are_unique = False
    return are_unique