code: def save(package, data, params={}, is_public=False):
      
      for key, value in params.items():
          if isinstance(value, np.ndarray):
              value = value.astype(float)
              params[key] = value.tolist()
      build_from_node(package, nodes.DataNode(None, None, data, params))
      push('{}'.format(package), is_public=is_public)
docs: Build and push data to Quilt registry at user/package/data_node,
      associating params as metadata for the data node.
      :param package: short package specifier string, i.e. 'team:user/pkg/subpath'
      :param data: data to save (np.ndarray or pd.DataFrame)
      :param params: metadata dictionary
      :param is_public: boolean kwarg to push the packages publicly