Refactor out the abundance of dictionary (un)packing
Instead, keep the dict packed once packed, and only unpack
it when needed.
"""
The md5 and sha modules are deprecated since Python 2.5, replaced by the
hashlib module containing both hash algorithms. Here, we provide a common
interface to the md5 and sha constructors, preferring the hashlib module when
available.
"""
try:
import hashlib
md5_constructor = hashlib.md5
sha_constructor = hashlib.sha1
except ImportError:
import md5
md5_constructor = md5.new
import sha
sha_constructor = sha.new