'Validate each set of coords'

def _validate_point(self, value):

    if (not isinstance(value, (list, tuple))):
        return 'Points    must    be    a    list    of    coordinate    pairs'
    elif (not (len(value) == 2)):
        return ('Value    (%s)    must    be    a    two-dimensional    point' % repr(value))
    elif ((not isinstance(value[0], (float, int))) or (not isinstance(value[1], (float, int)))):
        return ('Both    values    (%s)    in    point    must    be    float    or    int' % repr(value))
