'Remove multiple values from the cache.
This operation is idempotent (can be called multiple times, or on a
non-existent key, safely)
.. versionadded:: 0.5.0'

def delete_multi(self, keys):

    if self.key_mangler:
        keys = list(map((lambda key: self.key_mangler(key)), keys))
    self.backend.delete_multi(keys)
