Don't check for Jupyter in global scope and fix check (#3213)

Resolves #3208.

Prevent interactions with other libraries (pandas) that also access `get_ipython().config` and its parameters. See #3208 for details. I don't fully understand why this happens, but in spaCy, we can at least make sure we avoid calling into this method.

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spacy/displacy/__init__.py

@@ -9,10 +9,9 @@ from ..util import prints, is_in_jupyter
 
 
 _html = {}
-IS_JUPYTER = is_in_jupyter()
 
 
-def render(docs, style='dep', page=False, minify=False, jupyter=IS_JUPYTER,
+def render(docs, style='dep', page=False, minify=False, jupyter=False,
            options={}, manual=False):
     """Render displaCy visualisation.
 
@@ -39,7 +38,7 @@ def render(docs, style='dep', page=False, minify=False, jupyter=IS_JUPYTER,
     parsed = [converter(doc, options) for doc in docs] if not manual else docs
     _html['parsed'] = renderer.render(parsed, page=page, minify=minify).strip()
     html = _html['parsed']
-    if jupyter:  # return HTML rendered by IPython display()
+    if jupyter or is_in_jupyter():  # return HTML rendered by IPython display()
         from IPython.core.display import display, HTML
         return display(HTML(html))
     return html

spacy/util.py

@@ -222,15 +222,15 @@ def get_package_path(name):
 def is_in_jupyter():
     """Check if user is running spaCy from a Jupyter notebook by detecting the
     IPython kernel. Mainly used for the displaCy visualizer.
-
     RETURNS (bool): True if in Jupyter, False if not.
     """
+    # https://stackoverflow.com/a/39662359/6400719
     try:
-        cfg = get_ipython().config
+        shell = get_ipython().__class__.__name__
-        if cfg['IPKernelApp']['parent_appname'] == 'ipython-notebook':
+        if shell == "ZMQInteractiveShell":
-            return True
+            return True  # Jupyter notebook or qtconsole
     except NameError:
-        return False
+        return False  # Probably standard Python interpreter
     return False