| Segment reporting | The following tables summarize segment information for the three
and six months ended March 31, 2019 and 2018:   
    |  |  | Three Months Ended March 31, |  |  | Six Months Ended March 31, |  |  
    |  |  | 2018 |  |  | 2017 |  |  | 2018 |  |  | 2017 |  |  
    |  |  |  |  |  |  |  |  |  |  |  |  |  |  
    | Revenues |  |  |  |  |  |  |  |  |  |  |  |  |  
    | Retail and Online |  | $ | 25,747,635 |  |  | $ | 31,183,512 |  |  | $ | 56,392,650 |  |  | $ | 52,476,983 |  |  
    | Manufacturing |  |  | 21,062,147 |  |  |  | 20,808,622 |  |  |  | 43,444,432 |  |  |  | 39,687,157 |  |  
    | Services |  |  | 163,369 |  |  |  | 187,794 |  |  |  | 332,009 |  |  |  | 383,852 |  |  
    |  |  | $ | 46,973,151 |  |  | $ | 52,179,928 |  |  | $ | 100,169,091 |  |  | $ | 92,547,992 |  |  
    |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
    | Gross profit |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
    | Retail and Online |  | $ | 12,741,758 |  |  | $ | 14,536,885 |  |  | $ | 26,318,041 |  |  | $ | 25,992,687 |  |  
    | Manufacturing |  |  | 5,755,461 |  |  |  | 4,936,246 |  |  |  | 11,357,119 |  |  |  | 9,688,814 |  |  
    | Services |  |  | 153,930 |  |  |  | 177,570 |  |  |  | 313,067 |  |  |  | 365,090 |  |  
    |  |  | $ | 18,651,149 |  |  | $ | 19,650,701 |  |  | $ | 37,988,227 |  |  | $ | 36,046,591 |  |  
    |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
    | Operating income (loss) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
    | Retail and Online |  | $ | (129,237 | ) |  | $ | 2,391,848 |  |  | $ | (367,889 | ) |  | $ | 4,623,324 |  |  
    | Manufacturing |  |  | 2,022,072 |  |  |  | 1,504,823 |  |  |  | 4,192,549 |  |  |  | 3,007,077 |  |  
    | Services |  |  | 153,540 |  |  |  | 177,292 |  |  |  | 312,207 |  |  |  | 364,350 |  |  
    |  |  | $ | 2,046,375 |  |  | $ | 4,073,963 |  |  | $ | 4,136,867 |  |  | $ | 7,994,751 |  |  
    |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
    | Depreciation and amortization |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
    | Retail and Online |  | $ | 882,227 |  |  | $ | 440,503 |  |  | $ | 1,670,478 |  |  | $ | 1,117,964 |  |  
    | Manufacturing |  |  | 610,193 |  |  |  | 866,756 |  |  |  | 1,303,711 |  |  |  | 1,585,200 |  |  
    | Services |  |  | – |  |  |  | – |  |  |  | – |  |  |  | – |  |  
    |  |  | $ | 1,492,420 |  |  | $ | 1,307,259 |  |  | $ | 2,974,189 |  |  | $ | 2,703,164 |  |  
    |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
    | Interest expenses |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
    | Retail and Online |  | $ | 1,120,205 |  |  | $ | 1,349,291 |  |  | $ | 2,295,996 |  |  | $ | 3,371,698 |  |  
    | Manufacturing |  |  | 415,792 |  |  |  | 472,429 |  |  |  | 892,734 |  |  |  | 918,334 |  |  
    | Services |  |  | – |  |  |  | – |  |  |  | – |  |  |  | – |  |  
    |  |  | $ | 1,535,997 |  |  | $ | 1,821,720 |  |  | $ | 3,188,730 |  |  | $ | 4,290,032 |  |  
    |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
    | Net income before provision for income taxes |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
    | Retail and Online |  | $ | (1,332,758 | ) |  | $ | 1,161,581 |  |  | $ | (2,605,175 | ) |  | $ | 5,214,176 |  |  
    | Manufacturing |  |  | 1,854,486 |  |  |  | 1,019,656 |  |  |  | 5,066,106 |  |  |  | 2,083,049 |  |  
    | Services |  |  | 153,604 |  |  |  | 177,292 |  |  |  | 312,271 |  |  |  | 364,350 |  |  
    |  |  | $ | 675,332 |  |  | $ | 2,358,529 |  |  | $ | 2,773,202 |  |  | $ | 7,661,575 |  |     
    |  |  |  |  |  |  |  |  | As of |  |  | As of |  |  
    |  |  |  |  |  |  |  |  | March 31, |  |  | September 30, |  |  
    |  |  |  |  |  |  |  |  | 2019 |  |  | 2018 |  |  
    | Total assets |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
    | Retail and Online |  |  |  |  |  |  |  |  |  | $ | 83,439,817 |  |  | $ | 88,799,584 |  |  
    | Manufacturing |  |  |  |  |  |  |  |  |  |  | 48,335,629 |  |  |  | 52,915,109 |  |  
    | Services |  |  |  |  |  |  |  |  |  |  | 72,215 |  |  |  | 57,703 |  |  
    |  |  |  |  |  |  |  |  |  |  | $ | 131,847,661 |  |  | $ | 141,772,396 |  |  
    |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
    | Goodwill and intangible assets |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
    | Retail and Online |  |  |  |  |  |  |  |  |  | $ | 42,458,607 |  |  | $ | 43,268,668 |  |  
    | Manufacturing |  |  |  |  |  |  |  |  |  |  | 329,280 |  |  |  | 343,914 |  |  
    | Services |  |  |  |  |  |  |  |  |  |  | – |  |  |  | – |  |  
    |  |  |  |  |  |  |  |  |  |  | $ | 42,787,887 |  |  | $ | 43,612,582 |  |  
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