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"ImportError: cannot import name StanfordNERTagger" in NLTK

I'm unable to import the NER Stanford Tagger in NLTK. This is what I have done:

Downloaded the java code from here and added an environment variable STANFORD_MODELS with the path to the folder where the java code is stored.

That should be sufficient according to the information that is provided on the NLTK site. It says:

"Tagger models need to be downloaded from http://nlp.stanford.edu/software and the STANFORD_MODELS environment variable set (a colon-separated list of paths)."

Would anybody be kind enough to help me, please?

EDIT: The downloaded folder is located at /Users/-----------/Documents/JavaJuno/stanford-ner-2015-04-20 and contains these files:

LICENSE.txt         lib             ner.sh              stanford-ner-3.5.2-javadoc.jar
NERDemo.java            ner-gui.bat         sample-conll-file.txt       stanford-ner-3.5.2-sources.jar
README.txt          ner-gui.command         sample-w-time.txt       stanford-ner-3.5.2.jar
build.xml           ner-gui.sh          sample.ner.txt          stanford-ner.jar
classifiers         ner.bat             sample.txt

Then I have added an environment variable STANFORD_MODELS:

os.environ["STANFORD_MODELS"] = "/Users/-----------/Documents/JavaJuno/stanford-ner-2015-04-20"

Calling from nltk.tag import StanfordNERTagger yields the error: 

ImportError                               Traceback (most recent call last)
<ipython-input-356-f4287e573edc> in <module>()
----> 1 from nltk.tag import StanfordNERTagger

ImportError: cannot import name StanfordNERTagger

Also in case that this may be relevant, this is what is in my nltk.tag folder:

__init__.py api.pyc     crf.py      hmm.pyc     senna.py    sequential.pyc  stanford.py tnt.pyc
__init__.pyc    brill.py    crf.pyc     hunpos.py   senna.pyc   simplify.py stanford.pyc    util.py
api.py      brill.pyc   hmm.py      hunpos.pyc  sequential.py   simplify.pyc    tnt.py      util.pyc

EDIT2: I have managed to import the NER Tagger, by using:

from nltk.tag.stanford import NERTagger

but now when calling an example call from the NLTK website, I get:

In [360]: st = NERTagger('english.all.3class.distsim.crf.ser.gz')
---------------------------------------------------------------------------
LookupError                               Traceback (most recent call last)
<ipython-input-360-0c0ab770b0ff> in <module>()
----> 1 st = NERTagger('english.all.3class.distsim.crf.ser.gz')

/Library/Python/2.7/site-packages/nltk/tag/stanford.pyc in __init__(self, *args, **kwargs)
    158 
    159     def __init__(self, *args, **kwargs):
--> 160         super(NERTagger, self).__init__(*args, **kwargs)
    161 
    162     @property

/Library/Python/2.7/site-packages/nltk/tag/stanford.pyc in __init__(self, path_to_model, path_to_jar, encoding, verbose, java_options)
     40                 self._JAR, path_to_jar,
     41                 searchpath=(), url=_stanford_url,
---> 42                 verbose=verbose)
     43 
     44         self._stanford_model = find_file(path_to_model,

/Library/Python/2.7/site-packages/nltk/__init__.pyc in find_jar(name, path_to_jar, env_vars, searchpath, url, verbose)
    595                     (name, url))
    596     div = '='*75
--> 597     raise LookupError('\n\n%s\n%s\n%s' % (div, msg, div))
    598 
    599 ##########################################################################

LookupError: 

===========================================================================
  NLTK was unable to find stanford-ner.jar! Set the CLASSPATH
  environment variable.

  For more information, on stanford-ner.jar, see:
    <http://nlp.stanford.edu/software>
===========================================================================

So I have incorrectly set the environment variable. Can anybody help me with that?

Solution

  • I worked it out.

    1. set the STANFORD_MODELS as you did # I learnt from you, thx!
    2. import nltk.tag.stanford as st
    3. tagger = st.StanfordNERTagger(PATH_TO_GZ, PATH_TO_JAR) # here PATH_TO_GZ and PATH_TO_JAR are the FULL path to where I store the file "all.3class.distsim.crf.ser.gz" and the file "stanford-ner.jar"
    4. now the tagger is usable. # try tagger.tag(‘Rami Eid is studying at Stony Brook University in NY’.split())

    It has nothing to do with CLASSPATH.

    Hope it helps!