How to replace specific data of one df with another df based on a dictionary having row and column info

Question

suppose I have 2 df

df1
   A       B       C
0  1   Apple     WED
1  2  Pineapple  JYT
2  3    Tea      SDF

df2
   A       B       C
0  1   Apple     ABS
1  2  Banana     JYT
2  3    Cake     SDF
3  4   Apple     ABS
4  5    Cake     JYT
5  6    Cake     SDF

I want to replace df2 data with df1 based on a dict having values of column A . dict = {B:[2,3],C:[1]}

new df df3 will be

   A       B       C
0  1   Apple     WED
1  2  Pineapple  JYT
2  3    Tea      SDF
3  4   Apple     ABS
4  5    Cake     JYT
5  6    Cake     SDF

I tried by using iloc but failed.

Answer 1

First dont use dict for variable name, because python code word. Then extract values from first df1 to new DataFrame for only matched values and use DataFrame.update with set A to index for both DataFrame s:

d = {'B':[2,3],'C':[1]}

df11 = df1.set_index('A')
df12 = pd.concat({k:df11.loc[v, k] for k, v in d.items()}, axis=1)


df22 = df2.set_index('A')
df22.update(df12)
df = df22.reset_index()
print (df)
   A          B    C
0  1      Apple  WED
1  2  Pineapple  JYT
2  3        Tea  SDF
3  4      Apple  ABS
4  5       Cake  JYT
5  6       Cake  SDF