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 # LockPDF-Pro
 LockPDF Pro is a simple, lightweight software for encrypting and decrypting PDF files without altering the original copy. Operating entirely offline, it ensures document security from online threats. With a user-friendly interface, it allows easy addition or removal of passwords, maintaining the integrity and original content of your PDFs.
+
+### Acknowledgment:
+LockPDF Pro v1.0 incorporates the PyPDF2 library for PDF encryption and decryption,
+and Tkinter, a standard GUI toolkit in Python, for creating the graphical user 
+interface. We extend our gratitude to the developers and contributors of PyPDF2 
+and Tkinter for their valuable contributions to the open-source community.