mapping = {
'1000268201_693b08cb0e'  :  ['A child in a pink dress is climbing up a set  of stairs in an entry way .', 'A girl going into a wooden building .', 'A little girl climbing into a wooden playhouse .', 'A little girl climbing the stairs to her playhouse .', 'A little girl in a pink dress going into a wooden cabin .'],
'101654506_8eb26cfb60'   :  ['A brown and white dog is running through the snow .', 'A dog is running in the snow', 'A dog running through snow .', 'a white and brown dog is running through a snow covered field .', 'The white and brown dog is running over the surface of the snow .']
}
 
for i in mapping:
    for j in range(0,len(mapping[i])):
        mapping[i][j]=mapping[i][j].lower();
 
print(mapping)

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