Encrypt your pdf files in bulk.

encrypt_pdf.py

import PyPDF2


def encrypt_pdf(file_to_encrypt, password, save_file_as):

    pdf_writer = PyPDF2.PdfFileWriter()

    with open(file_to_encrypt, "rb") as pdf_input_file:
        pdf_reader = PyPDF2.PdfFileReader(pdf_input_file)
        for page_num in range(pdf_reader.numPages):
            page = pdf_reader.getPage(page_num)
            pdf_writer.addPage(page)

    pdf_writer.encrypt(password, use_128bit=True)

    with open(save_file_as, "wb") as result_pdf:
        pdf_writer.write(result_pdf)

    print(
        "Successfully encrypted pdf file!!",
        "saved as", save_file_as
    )


if __name__ == "__main__":
    file_to_encrypt = "encrypt_me.pdf"
    password = "qwerty123"
    save_file_as = "encrypted.pdf"
    encrypt_pdf(file_to_encrypt, password, save_file_as)

requirements.txt

PyPDF2==1.26.0