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Flatten list of dictionaries into dataframe columns

I have the following data which contain lists of dictionaries

data= [
 {'Time': 18057610.0,
  'Flux': [{'V0': -1.4209e-15},
   {'V1': 2.7353e-16},
   {'V2': 1.1935e-15},
   {'V3': 1.1624},
   {'V4': -6.1692e-15},
   {'V5': 3.2218e-15}]},
 {'Time': 18057620.4,
  'Flux': [{'V0': 2.4377e-16},
   {'V1': -6.2809e-15},
   {'V2': 1.6456e-15},
   {'V3': 1.1651},
   {'V4': 1.7147e-15},
   {'V5': 9.8872e-16}]},
 {'Time': 18057631.1,
  'Flux': [{'V0': 4.1124e-15},
   {'V1': 1.5598e-15},
   {'V2': -2.325e-16},
   {'V3': 1.1638},
   {'V4': -3.9983e-15},
   {'V5': 4.459e-16}]}]

I want to get something like this:

preferred_df:

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                     V0            V1  ...            V4            V5
Time                                    ...                            
18057610.0 -1.420900e-15  2.735300e-16  ... -6.169200e-15  3.221800e-15
18057620.4  2.437700e-16 -6.280900e-15  ...  1.714700e-15  9.887200e-16
18057631.1  4.112400e-15  1.559800e-15  ... -3.998300e-15  4.459000e-16

I came up with the following code which serves the purpose:

df = pd.DataFrame(data).explode('Flux').reset_index(drop=True)
df = df.join(pd.DataFrame(df.pop('Flux').values.tolist())).groupby('Time').sum()

However, I don’t want to use groupby and sum(). What are the other ways (dictionary comprehension?) to flatten the "Flux" column without getting the NaN values while flattening the dictionaries and get the preferred_df? I tried json_normalize() but got same NaNs and needed to use groupby() and sum().

>Solution :

Try:

df = pd.DataFrame(
    [{k: v for d2 in d["Flux"] for k, v in d2.items()} for d in data],
    index=[d["Time"] for d in data],
)
print(df)

Prints:

                      V0            V1            V2      V3            V4            V5
18057610.0 -1.420900e-15  2.735300e-16  1.193500e-15  1.1624 -6.169200e-15  3.221800e-15
18057620.4  2.437700e-16 -6.280900e-15  1.645600e-15  1.1651  1.714700e-15  9.887200e-16
18057631.1  4.112400e-15  1.559800e-15 -2.325000e-16  1.1638 -3.998300e-15  4.459000e-16
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