Draw an inner map of a certain place (like a house blueprint) in Django
Assuming you mean drawing plans interactively in the browser, rather than maps in the sense of Google Maps, you need something like HTML5 canvas or SVG, and a library like fabric.js (for canvas) or Raphael (for SVG). Your JS code will then handle the mechanics of drawing lines from mouse input, producing a picture in the browser. You can then extract that picture using JS and pass it back to the server for saving as a PNG or whatever. 
If you're targeting modern browsers, canvas is definitely the way to go - it's a much nicer API, has better libraries (IMO) and is easier to extract PNGs from. SVG isn't too bad, but getting PNGs out is tricky - it relies either on hacks (converting the SVG to canvas in JS, rendering it in an invisible element, then converting that to PNG!) or sending the whole SVG to the server to be rendered there. 
I've recently implemented something requiring very similar mechanics, although for a very different purpose, so if you have any more detailed questions feel free to ask.
i'll try to be the most specific possible. I have a Django project and i want to be able to draw a inner map of a certain place. By that, i mean a graphical representation of important objects like the tables positions, bathrooms etc. I'm trying to avoid Flash as an option. Is there an existing API that i can use? Or how can i get this thing working?
I don't mean to draw soemthing in 3d, just a simple view from above, like a blueprint.
Thanks in advance.