Avoid duplicates when creating text file

Avoid Duplicates when Creating Text File
- Python for Integrated Circuits -
- An Online Book -

Python for Integrated Circuits http://www.globalsino.com/ICs/

Chapter/Index: Introduction | A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | Appendix

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Avoid duplicates when creating text file:
a = "Yougui"
...
       with open(theFileOfTheSetOfImage, 'a') as f:
              if a != Lines[i]:
                     print(a)
                     print(Lines[i])
                     f.write(Lines[i])
                     a = Lines[i]
                     # f.write('\n')

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Appends a string to the end of a file only if it's not already a line in the file. Code:

Input:

Output:

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