Remove duplicates in DF and convert to JSON obj in python

name         series
=============================
a             a1
b             b1
a             a2
a             a1
b             b2

{
   "a": ["a1", "a2"],
   "b": ["b1", "b2"]
}

test = df.groupby("series")[["name"]].apply(lambda x: x)

Series
Name
A     0   A1
      2   A2
      3   A1
B     1   B1
      4   B2

out = df.drop_duplicates().groupby('name')['series'].agg(list).to_dict()

out = df.groupby('name')['series'].agg(lambda x: x.unique().tolist()).to_dict()

out = (df[['name', 'series']].drop_duplicates()
       .groupby('name')['series'].agg(list).to_dict()
      )

out = (df.groupby('name')['series']
         .agg(lambda x: sorted(x.unique().tolist())).to_dict()
      )

# input
  Name Series
0    A     Z1
1    B     B1
2    A     A2
3    A     Z1
4    B     B2

# output
{'A': ['A2', 'Z1'], 'B': ['B1', 'B2']}