text: 
  
  import pytest
  
  from jubox import JupyterNotebook, JupyterCell, RawCell
  from nbformat.notebooknode import NotebookNode
  
  from nbformat.v4 import new_code_cell
  
  def test_iter():
      
      nb = JupyterNotebook([
          RawCell("1 cell"),
          RawCell("2 cell"),
          RawCell("3 cell"),
      ])
  
      for i, cell in enumerate(nb):
          assert isinstance(cell, JupyterCell)
          assert cell["source"] == "{} cell".format(i+1)
  
  