gistfile1.py

# get all the open heads
heads = revs(repo, "head() & (! closed())")

# find the common ancestor of default and revision_number ...
ancestor = revs(repo, "ancestor(%d, default)"% revision_number )[0]
# ... then get the path of changes between the common ancestor
# and our original revision
path = revs(repo, "%d::%d"%(ancestor, revision_number))

# The above can also be done just as
path = revs(repo, "ancestor(%d, default)::%d" %(revision_number, revision_number))

# find all the revisions that change the files under patches/
patches = revs(repo, 'files("patches/*")')