x = "abcdef"
i = "i"
while i in x:
print(i, end="")
expected output=abcdef
actual output=nil
x = ['ab', 'cd']
for i in x:
i.upper()
print(x)
expected output= ['AB', 'CD']
actual output= ['ab', 'cd']
x = "abcdef"
i = "i"
while i in x:
print(i, end="")
expected output=abcdef
actual output=nil
x = ['ab', 'cd']
for i in x:
i.upper()
print(x)
expected output= ['AB', 'CD']
actual output= ['ab', 'cd']