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How do I tell python what my data structure (that is in binary) looks like so I can plot it?

I have a data set that looks like this.
b'\xa3\x95\x80\x80YFMT\x00BBnNZ\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00Type,Length,Name,Format,Columns\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xa3\x95\x80\x81\x17PARMNf\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00Name,Value\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xa3\x95\x80\x82-GPS\x00BIHBcLLeeEefI\x00\x00\x00Status,TimeMS,Week,NSats,HDop,Lat,Lng,RelAlt,Alt,Spd,GCrs,VZ,T\x00\x00\xa3\x95\x80\x83\x1fIMU\x00Iffffff\x00\x00\x00\x00\x00\x00\x00\x00\x00TimeMS,GyrX,GyrY,G
I have been reading around to try and find how do I implement a code into python that will allow me to parse this data so that I can plot some of the column against each other (Mostly time).
Some things I found that may help in doing this:
There is a code that will allow me to convert this data into a CSV file. I know how to use the code and convert it to a CSV file and plot from there, but for a learning experience I want to be able to do this without converting it to a CSV file. Now I tried reading that code but I am clueless since I am very new to python. Here is the link to the code:
https://github.com/PX4/Firmware/blob/master/Tools/sdlog2/sdlog2_dump.py
Also, Someone posted this saying this might be the log format, but again I couldn't understand or run any code on that page.
http://dev.px4.io/advanced-ulog-file-format.html

A good starting point for parsing binary data is the struct module https://docs.python.org/3/library/struct.html and it's unpack function. That's what the CSV dump routine you linked to is doing as well. If you walk through the process method, it's doing the following:
Read a chunk of binary data
Figure out if it has a valid header
Check the message type - if it's a FORMAT message parse that. If it's
a description message, parse that.
Dump out a CSV row
You could modify this code to essentially replace the __printCSVRow method with something that captures the data into a pandas dataframe (or other handy data structure) so that when the main routine is all done you can grab all the data from the dataframe and plot it.

Reading from a CSV file while it is being written to

So before I start I know this is not the proper way to go about doing this but this is the only method that I have for accessing the data I need on the fly.
I have a system which is writing telemetry data to a .csv file while it is running. I need to see some of this data while it is being written but it is not being broadcast in a manner which allows me to do this.
Question: How do I read from a CSV file which is being written to safely.
Typically I would open the file and look at the values but I am hoping to be able to write a python script which is able to examine the csv for me and report the most recent values written without compromising the systems ability to write to the file.
I have absolutely NO access to the system or the manner in which it is writing to the CSV I am only able to see that the CSV file is being updated as the system runs.
Again I know this is NOT the right way to do this but any help you could provide would be extremely helpful.
This is mostly being run in a Windows environment

You can do something like:
tailf csv_file | python your_script.py
and read from sys.stdin

create pdf from python

I'm looking to generate PDF's from a Python application.
They start relatively simple but some may become more complex (Essentially letter like documents but will include watermarks for example later)
I've worked in raw postscript before and providing I can generate the correct headers etc and file at the end of it I want to avoid use of complex libs that may not do entirely what I want. Some seem to have got bitrot and no longer supported (pypdf and pypdf2) Especially when I know PDF/Postscript can do exactly what I need. PDF content really isn't that complex.
I can generate EPS (Encapsulated postscript) fine by just writing the appropriate text headers to file and my postscript code. But Inspecting PDF's there is a lil binary header I'm not sure how to generate.
I could generate an EPS and convert it. I'm not overly happy with this as the production environment is a Windows 2008 server (Dev is Ubuntu 12.04) and making something and converting it seems very silly.
Has anyone done this before?
Am I being pedantic by not wanting to use a library?

borrowed from ask.yahoo
A PDF file starts with "%PDF-1.1" if it is a version 1.1 type of PDF file. You can read PDF files ok when they don't have binary data objects stored in them, and you could even make one using Notepad if you didn't need to store a binary object like a Paint bitmap in it.
But after seeing the "%PDF-1.1" you ignore what's after that (Adobe Reader does, too) and go straight to the end of the file to where there is a line that says "%%EOF". That's always the last thing in the file; and if that's there you know that just a few characters before that place in the file there's the word "startxref" followed by a number. This number tells a reader program where to look in the file to find the start of the list of items describing the structure of the file. These items in the list can be page objects, dictionary objects, or stream objects (like the binary data of a bitmap), and each one has "obj" and "endobj" marking out where its description starts and ends.
For fairly simple PDF files, you might be able to type the text in just like you did with Notepad to make a working PDF file that Adobe Reader and other PDF viewer programs could read and display correctly.
Doing something like this is a challenge, even for a simple file, and you'd really have to know what you're doing to get any binary data into the file where it's supposed to go; but for character data, you'd just be able to type it in. And all of the commands used in the PDF are in the form of strings that you could type in. The hardest part is calculating those numbers that give the file offsets for items in the file (such as the number following "startxref").
If the way the file format is laid out intrigues you, go ahead and read the PDF manual, which tells the whole story.
http://www.adobe.com/content/dam/Adobe/en/devnet/acrobat/pdfs/PDF32000_2008.pdf
but really you should probably just use a library
Thanks to #LukasGraf for providing this link http://www.gnupdf.org/Introduction_to_PDF that shows how to create a simple hello world pdf from scratch

As long as you're working in Python 2.7, Reportlab seems to be the best solution out there at the moment. It's quite full-featured, and can be a little complex to work with, depending on exactly what you're doing with it, but since you seem to be familiar with PDF internals in general hopefully the learning curve won't be too steep.

I recommend you to use a library. I spent a lot of time creating pdfme and learned a lot of things along the way, but it's not something you would do for a single project. If you want to use my library check the docs here.

How do I access both binary and text data for email processing with Python 3?

I am converting a Python 2 program to Python 3 and I'm not sure about the approach to take.
The program reads in either a single email from STDIN, or file(s) are specified containing emails. The program then parses the emails and does some processing on them.
SO we need to work with the raw data of the email input, to store it on disk and do an MD5 hash on it. We also need to work with the text of the email input in order to run it through the Python email parser and extract fields etc.
With Python 3 it is unclear to me how we should be reading in the data. I believe we need the raw binary data in order to do an md5 on it, and also to be able to write it to disk. I understand we also need it in text form to be able to parse it with the email library. Python 3 has made significant changes to the IO handling and text handling and I can't see the "correct" approach to read the email raw data and also use the same data in text form.
Can anyone offer general guidance on this?

The general guidance is convert everything to unicode ASAP and keep it that way until the last possible minute.
Remember that str is the old unicode and bytes is the old str.
See http://docs.python.org/dev/howto/unicode.html for a start.
With Python 3 it is unclear to me how we should be reading in the data.
Specify the encoding when you open the file it and it will automatically give you unicode. If you're reading from stdin, you'll get unicode. You can read from stdin.buffer to get binary data.
I believe we need the raw binary data in order to do an md5 on it
Yes, you do. encode it when you need to hash it.
and also to be able to write it to disk.
You specify the encoding when you open the file you're writing it to, and the file object encodes it for you.
I understand we also need it in text form to be able to parse it with the email library.
Yep, but since it'll get decoded when you open the file, that's what you'll have.
That said, this question is really too open ended for Stack Overflow. When you have a specific problem / question, come back and we'll help.

Python file to read in binary and write in xml

I have a binary file which was created by a VBA file (I don't work with VBA or binary at all) but I need to get Python to read this binary file (which includes a list of inputs for a calculation) and then write these values into an xml file.
If I know the order of the inputs into the file that is created, is it possible to read the binary code line by line, to get input by input and then write into the xml?
I have to use Python rather than VBA since I am not authorised to change the original VBA files.
I apologise for the lack of information, I only know a bit of Python and have never worked with VBA or binary. I really appreciate any help anyone can give me! Thank you =)

If you have the VBA code that made the file you should be able to copy the data structure in python and then deserialize it.

Python is probably not the best tool, I would recommend VBA as it is going to be best suited to reading that file. Then, create your xml file as output.