I need sequence embedding but it shows TypeError: list indices must be integers or slices, not str

I need sequence embedding but it shows TypeError: list indices must be integers or slices, not str

import pandas as pd
data = [[100, 'MLARALLL'], [101, 'MEAEGSSAPARA'], [102, 'MPGPRRPAGSR']]
df = pd.DataFrame(data, columns = ['Id', 'Sequence'])
seqlist = [list(x) for x in df.Sequence.values]
#install SGT
from sgt import SGT
sgt = SGT(kappa=10, lengthsensitive = False)
embedding = sgt.fit_transform(corpus=seqlist)
#this line creates list containing embedding vectors for the dataframe sequences