Fix CI By Adding PIP to conda envt for docs build

docs/environment.yml

@@ -12,5 +12,6 @@ dependencies:
 - tornado
 - entrypoints
 - ipykernel
+- pip
 - pip:
     - nbsphinx>=0.7.1

docs/source/nbconvert_library.ipynb

@@ -46,7 +46,7 @@
    "source": [
     "from urllib.request import urlopen\n",
     "\n",
-    "url = 'http://jakevdp.github.com/downloads/notebooks/XKCD_plots.ipynb'\n",
+    "url = 'https://jakevdp.github.io/downloads/notebooks/XKCD_plots.ipynb'\n",
     "response = urlopen(url).read().decode()\n",
     "response[0:60] + ' ...'"
    ]

docs/source/removing_cells.rst

@@ -15,7 +15,7 @@ Removing pieces of cells using cell tags
 The most straightforward way to control which pieces of cells are
 removed is to use **cell tags**. These are single-string snippets of
 metadata that are stored in each cells "tag" field. The
-`TagRemovePreprocessor` can be used 
+`TagRemovePreprocessor` can be used
 to remove inputs, outputs, or entire cells.
 
 For example, here is a configuration that uses a different tag for
@@ -27,17 +27,33 @@ we demonstrate using the nbconvert Python API.
    from traitlets.config import Config
    import nbformat as nbf
    from nbconvert.exporters import HTMLExporter
+   from nbconvert.preprocessors import TagRemovePreprocessor
 
+   # Setup config
    c = Config()
 
-   # Configure our tag removal
+   # Configure tag removal - be sure to tag your cells to remove  using the
+   # words remove_cell to remove cells. You can also modify the code to use
+   # a different tag word
    c.TagRemovePreprocessor.remove_cell_tags = ("remove_cell",)
    c.TagRemovePreprocessor.remove_all_outputs_tags = ('remove_output',)
    c.TagRemovePreprocessor.remove_input_tags = ('remove_input',)
+   c.TagRemovePreprocessor.enabled = True
 
    # Configure and run out exporter
-   c.HTMLExporter.preprocessors = ["TagRemovePreprocessor"]
-   HTMLExporter(config=c).from_filename("path/to/mynotebook.ipynb")
+   c.HTMLExporter.preprocessors = ["nbconvert.preprocessors.TagRemovePreprocessor"]
+
+   exporter = HTMLExporter(config=c)
+   exporter.register_preprocessor(TagRemovePreprocessor(config=c),True)
+
+   # Configure and run our exporter - returns a tuple - first element with html,
+   # second with notebook metadata
+   output = HTMLExporter(config=c).from_filename("your-notebook-file-path.ipynb")
+
+   # Write to output html file
+   with open("your-output-file-name.html",  "w") as f:
+       f.write(output[0])
+
 
 Removing cells using Regular Expressions on cell content
 --------------------------------------------------------
@@ -63,4 +79,3 @@ an arbitrary number of whitespace characters followed by the end of the string.
 See https://regex101.com/ for an interactive guide to regular expressions
 (make sure to select the python flavor). See https://docs.python.org/library/re.html
 for the official regular expression documentation in python.
-