Draw dendrogram in python manually

Code to implement scipy dendrogram can be found here and this simple implementation will help you to move on.

perhaps an other solution could be this one: http://ete.cgenomics.org/ I recommend you the main help pdf to start: http://ete.cgenomics.org/releases/ete2/doc/ete_tutorial.pdf

The ETE python toolkit gives you a lot of possibilities for tree drawing. The drawing engine allows for programmatic tree rendering. Trees can be plotted as PNG or SVG images. Dendrograms can be represented as rectangular or circular tress.

Although ETE is commonly used to deal with phylogenetic trees, it provides also a clustering module, with several special predefined visualization modes.

Check some examples at http://packages.python.org/ete2/tutorial/tutorial_drawing.html