I used a for loop to calculate a series of thresholds for diff segments in an image.

```
>>crdf
[(11, 6),
 (11, 7),
 (11, 11),
 (12, 16),
 (10, 9),
 (21, 26),
 (15, 15),
 (12, 17),
 (12, 12),
 (14, 10),
 (20, 26)
]

>>for i in range(0,4):
>>    print(threshold_otsu(img[crdf[i]],16))

-14.606459
-15.792943
-15.547393
-16.170353

```

How to calculate the mean of these thresholds(output values) and store it in a variable using python?