Pandas - Use Groupby And Filter On Multiple Conditions

I am trying to group a dataset by IDs, then by time. Then, I want to select records based on the criteria of one column and based on time by ID. I have been researching and playing

Solution 1:

We need groupby + shift ,

df.loc[(df.groupby(["a"]).value2.shift()+df.value2).eq('OrangeApple'),'a']
Out[287]: 
2    A1
6    A3
9    A2
Name: a, dtype: object


df.loc[(df.groupby(["a"]).value2.shift()+df.value2).eq('OrangeApple'),'a'].nunique()
Out[288]: 3