from PyPDF2 import PdfFileMerger
merger = PdfFileMerger()
input1 = open("C:\\Users\\laiwu\\Desktop\\rmrb\\test1.pdf", "rb")
input2 = open("C:\\Users\\laiwu\\Desktop\\rmrb\\test2.pdf", "rb")
input3 = open("C:\\Users\\laiwu\\Desktop\\rmrb\\test3.pdf", "rb")
# add the first 3 pages of input1 document to output
#将test1.pdf前三页放入output.pdf
merger.append(fileobj = input1, pages = (0,3))
# insert the first page of input2 into the output beginning after the second page
#将test2.pdf的第一页插入output.pdf的第三页
merger.merge(position = 2, fileobj = input2, pages = (0,1))
# append entire input3 document to the end of the output document
#将test3.pdf全部内容放入output.pdf最后
merger.append(input3)
# Write to an output PDF document
output = open("C:\\Users\\laiwu\\Desktop\\rmrb\\output.pdf", "wb")
merger.write(output)