new_contents: 
  from django.conf import settings
  from django.core.cache.backends.base import BaseCache
  from django.core.exceptions import ImproperlyConfigured
  
  import lmdb
  
  
  class LmdbCache(BaseCache):
  
      def __init__(self, params):
          super(LmdbCache, self).__init__(params)
          # Rip other options out of params
          self.env = lmdb.open(params['LOCATION'])
  
      def add(self, key, value, timeout=DEFAULT_TIMEOUT, version=None):
          key = self.make_key(key, version=version)
          return self.env.put(key, value, overwrite=False)
  
      def get(self, key, default=None, version=None):
          key = self.make_key(key, version=version)
          return self.env.get(key, default=default)
  
      def set(self, key, value, timeout=DEFAULT_TIMEOUT, version=None):
          key = self.make_key(key, version=version)
          self.env.put(key, value, overwrite=True)
  
      def delete(self, key, version=None):
          key = self.make_key(key, version=version)
          self.env.delete(key)
      def clear(self):
  
      # Optional
      #def has_key(self, key, version=None):
      #def incr(self, key, delta=1, version=None):
      #def decr(self, key, delta=1, version=None):
      #def get_many(self, keys, version=None):
      #def set_many(self, data, timeout=DEFAULT_TIMEOUT, version=None):
      #def delete_many(self, keys, version=None):
  
  
subject: Add the code