Check out example codes for "TypeError: takes 0 positional arguments but 1 was given python". It will help you in understanding the concepts better.
Code Example 1
When Python tells you "generatecode() takes 0 positional arguments but 1 was given", it's telling you that your method is set up to take no arguments, but the self argument is still being passed when the method is called, so in fact it is receiving one argument. Adding self to your method definition should resolve the problem.
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