Help With While Loop and Append

[laprus]

Hi everyone. I am using python for coding an algorithm and I'm struggling with usage of while and append.

the part of code is:

print('isis')
print(temp11)
print(main_list[9][6])  # this variable's value is different now
temp_cluster.clear()
print(temp_cluster)
temp_cluster.append(Node_Names[temp11])
print(main_list[9][6])   # and the same variable's value is different now

Later on, I am changing main_list[9][6] to temp_cluster. but that is after the above sentences.
However the value of variable changes midway.

Here is same output:

Output:
isis
  10
  ['j', 'i']    # as you can see value has changed from 'j' 'i' to 'k' after 2 sentences
  []
  ['k']
  exy

Can anyone help me with this?