code: def open_consolidated(store, metadata_key='.zmetadata', mode='r+', **kwargs):
      
  
      from .storage import ConsolidatedMetadataStore
  
      # normalize parameters
      store = normalize_store_arg(store)
      if mode not in {'r', 'r+'}:
          raise ValueError("invalid mode, expected either 'r' or 'r+'; found {!r}"
                           .format(mode))
  
      # setup metadata sotre
      meta_store = ConsolidatedMetadataStore(store, metadata_key=metadata_key)
  
      # pass through
      return open(store=meta_store, chunk_store=store, mode=mode, **kwargs)
docs: Open group using metadata previously consolidated into a single key.
  
      This is an optimised method for opening a Zarr group, where instead of
      traversing the group/array hierarchy by accessing the metadata keys at
      each level, a single key contains all of the metadata for everything.
      For remote data sources where the overhead of accessing a key is large
      compared to the time to read data.
  
      The group accessed must have already had its metadata consolidated into a
      single key using the function :func:`consolidate_metadata`.
  
      This optimised method only works in modes which do not change the
      metadata, although the data may still be written/updated.
  
      Parameters
      ----------
      store : MutableMapping or string
          Store or path to directory in file system or name of zip file.
      metadata_key : str
          Key to read the consolidated metadata from. The default (.zmetadata)
          corresponds to the default used by :func:`consolidate_metadata`.
      mode : {'r', 'r+'}, optional
          Persistence mode: 'r' means read only (must exist); 'r+' means
          read/write (must exist) although only writes to data are allowed,
          changes to metadata including creation of new arrays or group
          are not allowed.
      **kwargs
          Additional parameters are passed through to :func:`zarr.creation.open_array` or
          :func:`zarr.hierarchy.open_group`.
  
      Returns
      -------
      g : :class:`zarr.hierarchy.Group`
          Group instance, opened with the consolidated metadata.
  
      See Also
      --------
      consolidate_metadata