'Calculate mean value by interval coordinates in pandas

I have a dataframe such as :

Name Position Value
A    1        10
A    2        11
A    3        10
A    4        8
A    5        6
A    6        12
A    7        10
A    8        9
A    9        9
A    10       9
A    11       9
A    12       9

and I woulde like for each interval of 3 position, to calculate the mean of Values. And create a new df with start and end coordinates (of length 3 then), with the Mean_value column.

Name Start End Mean_value 
A    1     3   10.33     <---- here this is (10+11+10)/3 = 10.33 
A    4     6   8.7
A    7     9   9.3
A    10    13  9 

Does someone have an idea using pandas please ?



Sources

This article follows the attribution requirements of Stack Overflow and is licensed under CC BY-SA 3.0.

Source: Stack Overflow

Solution Source