OSError: [E050] Can't find model 'en'

I am trying to use this pytextrank library of python- https://github.com/DerwenAI/pytextrank/blob/master/example.ipynb but i am unable to resolve this error , earlier i was getting an error that ip.json can't be found, but then was resolved

    import pytextrank
    import sys
    path_stage0="data/ip.json" 
    path_stage1="o1.json"

    with open(path_stage1,'w') as f:
        for graf in pytextrank.parse_doc(pytextrank.json_iter(path_stage0)):
            f.write("%s\n" % pytextrank.pretty_print(graf._asdict()))
            print(pytextrank.pretty_print(graf))


    OSError                                   Traceback (most recent call last)
    <ipython-input-12-a20b437ea0f1> in <module>
          6 
          7 with open(path_stage1,'w') as f:
    ----> 8     for graf in pytextrank.parse_doc(pytextrank.json_iter(path_stage0)):
          9         f.write("%s\n" % pytextrank.pretty_print(graf._asdict()))
         10         print(pytextrank.pretty_print(graf))

~\Anaconda3\lib\site-packages\pytextrank\pytextrank.py in parse_doc(json_iter)
    259                 print("graf_text:", graf_text)
    260 
--> 261             grafs, new_base_idx = parse_graf(meta["id"], graf_text, base_idx)
    262             base_idx = new_base_idx
    263 

~\Anaconda3\lib\site-packages\pytextrank\pytextrank.py in parse_graf(doc_id, graf_text, base_idx, spacy_nlp)
    185     if not spacy_nlp:
    186         if not SPACY_NLP:
--> 187             SPACY_NLP = spacy.load("en")
    188 
    189         spacy_nlp = SPACY_NLP

~\Anaconda3\lib\site-packages\spacy\__init__.py in load(name, **overrides)
     25     if depr_path not in (True, False, None):
     26         deprecation_warning(Warnings.W001.format(path=depr_path))
---> 27     return util.load_model(name, **overrides)
     28 
     29 

~\Anaconda3\lib\site-packages\spacy\util.py in load_model(name, **overrides)
    137     elif hasattr(name, "exists"):  # Path or Path-like to model data
    138         return load_model_from_path(name, **overrides)
--> 139     raise IOError(Errors.E050.format(name=name))
    140 
    141 

OSError: [E050] Can't find model 'en'. It doesn't seem to be a shortcut link, a Python package or a valid path to a data directory.