diff --git a/src/allmydata/chunk.py b/src/allmydata/chunk.py
index 59a2c08cf..c3342bc14 100644
--- a/src/allmydata/chunk.py
+++ b/src/allmydata/chunk.py
@@ -47,8 +47,6 @@ or implied.  It probably won't make your computer catch on fire,
 or eat  your children, but it might.  Use at your own risk.
 """
 
-import sha
-
 from allmydata.util.hashutil import tagged_hash, tagged_pair_hash
 
 __version__ = '1.0.0-allmydata'
@@ -56,13 +54,6 @@ __version__ = '1.0.0-allmydata'
 BLOCK_SIZE     = 65536
 MAX_CHUNK_SIZE = BLOCK_SIZE + 4096
 
-def hash(s):
-  """
-  Cryptographic hash function used by this module.
-  """
-  return sha.new(s).digest()
-
-
 def roundup_pow2(x):
   """
   Round integer C{x} up to the nearest power of 2.