Pandas dataframe only select the columns that have all True

Try iterating through it and putting the keys in a list (you can easily modify this to result in a dict, though).

result = []
for i in df.keys():
    if df[i].all():
        result.append(i)

Try boolean indexing with all (for only True values):

df.columns[df.all()]

Output:

Index(['A', 'C', 'E'], dtype='object')