Sometimes, it is desired that you want to give option where a user can click a link and it will pop up a "File Download" dialogue box to the user instead of displaying actual content. This is very easy and can be achieved through HTTP header.
For example, if you want make a FileName file downloadable from a given link, then its syntax is as follows −
#!/usr/bin/python
# HTTP Header
print "Content-Type:application/octet-stream; name = \"FileName\"\r\n";
print "Content-Disposition: attachment; filename = \"FileName\"\r\n\n";
# Actual File Content will go here.
fo = open("foo.txt", "rb")
str = fo.read();
print str
# Close opend file
fo.close()