[Python] Pandas: how to map values in a column of lists?

A column in a pandas dataframe contains lists of values.

Using a dictionary, I would like to create a new column with mapped values using the dictionary, and for any values not in the dictionary, those values are removed.

Here is a minimal example:

Set up of the dataframe

df = pd.DataFrame(data={ 'B': ['x', 'y', 'z']})
df.at[0, 'B'] = ['jki', 'gg4', 'k6k']
df.at[1, 'B'] = ['2f4', 'gg4', 'g24']
df.at[2, 'B'] = ['1k1', 'g24', '1k1', '2f4']


Results in

df

B
0 [jki, gg4, k6k]
1 [2f4, gg4, g24]
2 [1k1, g24, 1k1, 2f4]


Set up of the dictionary

conv = { 'jki': 1, 'gg4': 2, '2f4': 3 , 'g24':4, }


If the column was not a list, this code would be used

df['MappedA'] = df.B.map(conv)


But since the column contains lists, that code can not be used

Here's what I would like the result to be

B MappedA
0 [jki, gg4, k6k] [ 1 , 2 ]
1 [2f4, gg4, g24] [3, 2, 4]
2 [1k1, g24, 1k1, 2f4] [ 4 , 3 ]

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