我一直在用Python创建一个程序，用于将2个PDF文件合并为一个文件。下面是代码：-

import os
from PyPDF2 import PdfFileMerger

source_dir = os.getcwd()

merger = PdfFileMerger()

for item in os.listdir(source_dir):
    if item.endswith('pdf'):
        merger.append(item)

merger.write('completed_file.pdf')
merger.close()

运行代码时遇到以下错误：-

"F:\Python folder\Pdf_Merger\venv\Scripts\python.exe" "F:/Python folder/Pdf_Merger/main.py"
Traceback (most recent call last):
  File "F:\Python folder\Pdf_Merger\venv\lib\site-packages\PyPDF2\pdf.py", line 1147, in getNumPages
    self.decrypt('')
  File "F:\Python folder\Pdf_Merger\venv\lib\site-packages\PyPDF2\pdf.py", line 1987, in decrypt
    return self._decrypt(password)
  File "F:\Python folder\Pdf_Merger\venv\lib\site-packages\PyPDF2\pdf.py", line 1996, in _decrypt
    raise NotImplementedError("only algorithm code 1 and 2 are supported")
NotImplementedError: only algorithm code 1 and 2 are supported

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "F:\Python folder\Pdf_Merger\main.py", line 10, in <module>
    merger.append(item)
  File "F:\Python folder\Pdf_Merger\venv\lib\site-packages\PyPDF2\merger.py", line 203, in append
    self.merge(len(self.pages), fileobj, bookmark, pages, import_bookmarks)
  File "F:\Python folder\Pdf_Merger\venv\lib\site-packages\PyPDF2\merger.py", line 139, in merge
    pages = (0, pdfr.getNumPages())
  File "F:\Python folder\Pdf_Merger\venv\lib\site-packages\PyPDF2\pdf.py", line 1150, in getNumPages
    raise utils.PdfReadError("File has not been decrypted")
PyPDF2.utils.PdfReadError: File has not been decrypted

Process finished with exit code 1