def METHOD_NAME():
    c = ct.EnsureFloat()
    # this should always work
    assert_equal(c(7.0), 7.0)
    assert_equal(c(7), 7.0)
    assert_equal(c('7'), 7.0)
    assert_equal(c([7.0, '3.0']), [7.0, 3.0])
    # this should always fail
    assert_raises(ValueError, lambda: c('fail'))
    assert_raises(ValueError, lambda: c([3.0, 'fail']))