Need a Python programmer to help me organize my creative writing process

I Am a writer, and my creative method is very confusing. I write poetry and prose, about several matters. So while I'm creating, I use a text file on the computer, and maintain one idea per line (some of them multiline, paragraph), but I'll go on writing about whatever comes to my mind. If that wasn't enough, it is pretty common for me to make a copy of a file of writings, and the correct or rewrite or add things to some of the lines(fragments). And save again. So in the end I have a lot of different files, on several topics, mixed up, with duplicates and semi-duplicates hanging around. I organize myself to know which file came first, because the order is important both at file level, and also inside the file: the order of fragments. So I have realized I can have some python code help me organize all that stuff! I know a little Python and coding, but I lack both time and knowledge to do this task. This is why I'm reaching to you. At first, I would need some code that would: Join file1 + file2 + file3 (all files on directory) into a single file, maintaining the original order of lines/paragraphs/fragments, deleting duplicate lines, and stating inside the Final File where each file starts and finishes. Also, the lines/fragments are not numbered on my text files, and I need them to be numbered in order at FinalText. Also, I need the code to be documented (to the surface only), so I can understand it and change it if needed be. One last thing: first line should state the date and time that FinalText was generated, and joining which txt exactly. Most of the fragments consist of text only, with multiple phrases or 1 phrase only or 1 word only, but some fragments consists of numbers and math operations. Each file has around 3000 fragments, and average 650kb or so. So as an example, imagine I have 3 files with inside content, which I want to join with this script, to create FinalText.txt. Check attachment This is the code I need for now. As in a .py file. I know how to run that on my directory, through terminal. If it's done right, in time, for a good price, etc, I have further stuff to ask to make the code help me even more! Thanks, Pedro