List all files of a specified file type inside a directory and its subdirectories, and copy them to a separate folder with no subdirectories

copy_files_to_folder.py

import os
import shutil

folder_path = '/path/to/source/folder/'
export_path = '/path/to/export/folder'
number_of_files = 0

for dirs, subdirs, files in os.walk(folder_path):
    number_of_files = number_of_files+len(files)
    for file in files:
        if file.endswith(".pdf"):
            print(file)
            filepath = dirs + os.sep + file
            print("Copying " + filepath)
            shutil.copy2(filepath, export_path)
            print('-----------')
print("Exported " + str(number_of_files) + " files to " + export_path + ".")