for instance, I have this sample dataframe

```
    Depth  Fluid

0   235.5  nan
1   236    water
2   236.5  water
3   237    nan
4   237.5  water
5   238    water

```

Now i want to get the sample data just to be like this

```
    Min_Depth  Max_Depth  Fluid

0   236        236.5      water
1   237.5      238        water

```

I have read about `pandas groupby` and `shift` method, the logic is if previous value is still the same (water) then group it, and use `min` and `max` to get the `Depth`, but I'm not sure if I can build the code something like what I want. I'm new in Python, I appreciate very much if someone can help me to write the code. Thanks!