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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def alphanumeric_hash(s: str, size=5):
 """Short alphanumeric string derived from hash of given string"""

  import hashlib
  import base64
  hash_object = hashlib.md5(s.encode('ascii'))
  s = base64.b32encode(hash_object.digest())
  result = s[:size].decode('ascii').lower()
  return result