QST:  how to use groupby.rolling correctly? Please help. Not sure what I am doing wrong
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#### Question about pandas

Hi there, my understanding of the df.groupby.rolling for a multi index dataframe should preserve the level-1 index, but I can't seem to get that. I am running Pandas 1.2.4. Hope that somebody can provide some insight of what is happening

```python
x = range(0, 6)
id = ['a', 'a', 'a', 'b', 'b', 'b']
temp = pd.DataFrame(zip(id, x), columns = ['id', 'x'])
temp['sequence']=[0,1,2,0,1,2]
temp=temp.set_index(['id','sequence'])
print(temp)

             x
id sequence   
a  0         0
   1         1
   2         2
b  0         3
   1         4
   2         5

temp.groupby(level=0,group_keys=True).rolling(2, min_periods=1).min()

      x
id     
a   0.0
a   0.0
a   1.0
b   3.0
b   3.0
b   4.0



```
base don the online guides, I would expect the level 1 index to be preserved...but I can't understand what is currently happening at this case? or what is the correct way of doing it.

Hope that somebody can provide some insights with regards to this problem

EDIT: Edited as text for readability, apologies for posting images earlier, forgot about it while posting it just now


