`saved_model.load` and `saved_model.main_op`, which will be replaced by
        `saved_model.main_op` in V2.
    *   Deprecate tf.QUANTIZED_DTYPES. The official new symbol is
        tf.dtypes.QUANTIZED_DTYPES.
    *   Update sklearn imports for deprecated packages.
    *   Deprecate `Variable.count_up_to` and `tf.count_up_to` in favor of
        `Dataset.range`.

0-6.  The min_range and max_range values are therefore 0.0 and 6.0.
Dequantize on quint8 will take each value, cast to float, and multiply
by 6 / 255.
Note that if quantizedtype is qint8, the operation will additionally add
each value by 128 prior to casting.

If the mode is 'MIN_FIRST', then this approach is used:

```c++
num_discrete_values = 1 << (# of bits in T)