code: def __call__(self, a, order=None):
      shape = (0,) * a.ndim
      order = a.order if order is None else order
      return self.new_tensor([a], shape, order=order)
  
file_path: mars/mars/tensor/datastore/core.py
imports: from ..operands import TensorHasInput, TensorOperandMixin
label_desc: Use image node_id 2 for calling the TensorDataStore obj's underlying member method code with example usage: obj.__call__(a, order) and returns: self