I haven't been able to find any way of providing a query parameter specifying date interval, so I'm afraid you'll have to retrieve all entries and filter them by date afterwards:
import feedparser
d = feedparser.parse('http://www.reddit.com/r/Python/.rss')
for entry in d.entries:
date = entry.published_parsed
if date.tm_year == 2015 and date.tm_mon == 4 and date.tm_mday >= 15 and date.tm_mday <= 16:
print entry.title