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        + `Max frequency` and `min frequency` are in range `± 5` of `average frequency`.

    + Batches must be relatively equally divided: 2 cases

        + *Case 1* : for all batches:  `normal batch size` ≤ `batch size` ≤ `normal batch size + (minimum batch size - 1)`.

         **E.g.**: `normal batch size` = 20, `minimum batch size` = 5 => 20 ≤ `average batch size` ≤ 24. 

		+ *Case 2* : Accept only one batch that:  `minimum batch size` ≤ `batch size` < `normal batch size`

        and the rest has the size of `normal batch size`. **E.g.**: `normal batch size` = 20, `minimum batch size` = 5,

		+ *Case 2* : Accept only one batch that:  `minimum batch size` ≤ `batch size` < `normal batch size` and the rest has the size of `normal batch size`. 

        **E.g.**: `normal batch size` = 20, `minimum batch size` = 5, `46` tuples => 2 batches with size of `20`, 1 batch with size of `6`

##### 2. Functional Tests