title: Altair - Issues setting-up
body: <p>I only have four-days of python experience. I am running the latest release of Anaconda 1.9.2;</p>
  
  <p>I am trying to run altair, for this I followed the official installation <a href="https://altair-viz.github.io/getting_started/installation.html" rel="nofollow noreferrer">instructions</a>:</p>
  
  <pre><code>conda install -c conda-forge altair vega_datasets
  </code></pre>
  
  <p>Using Coda navigator - environments I can see correctly installed are Altair (4.0.1), vega (2.6.0) and vega-datasets (0.8.0);</p>
  
  <p>I have checked al dependencies mentioned on Altair github and manually installed some that were missing (ie m2r and flake 8)</p>
  
  <p>However running the example plot in jupyter notebook;</p>
  
  <pre><code>import altair as alt
  import pandas as pd
  
  # for the notebook only (not for JupyterLab) run this command once per session
  alt.renderers.enable('notebook')
  
  source = pd.DataFrame({
      'a': ['A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I'],
      'b': [28, 55, 43, 91, 81, 53, 19, 87, 52]
  })
  
  alt.Chart(source).mark_bar().encode(
      x='a',
      y='b'
  )
  </code></pre>
  
  <p>outputs:</p>
  
  <pre><code>---------------------------------------------------------------------------
  NoSuchEntryPoint                          Traceback (most recent call last)
  ~\Anaconda3\lib\site-packages\altair\utils\plugin_registry.py in _enable(self, name, **options)
      133             try:
  --&gt; 134                 ep = entrypoints.get_single(self.entry_point_group, name)
      135             except entrypoints.NoSuchEntryPoint:
  
  ~\Anaconda3\lib\site-packages\entrypoints.py in get_single(group, name, path)
      216 
  --&gt; 217     raise NoSuchEntryPoint(group, name)
      218 
  
  NoSuchEntryPoint: No 'notebook' entry point found in group 'altair.vegalite.v4.renderer'
  
  During handling of the above exception, another exception occurred:
  
  ValueError                                Traceback (most recent call last)
  &lt;ipython-input-2-5584a45a74ac&gt; in &lt;module&gt;
        3 
        4 # for the notebook only (not for JupyterLab) run this command once per session
  ----&gt; 5 alt.renderers.enable('notebook')
        6 
        7 source = pd.DataFrame({
  
  ~\Anaconda3\lib\site-packages\altair\utils\plugin_registry.py in enable(self, name, **options)
      169         if name is None:
      170             name = self.active
  --&gt; 171         return PluginEnabler(self, name, **options)
      172 
      173 
  
  ~\Anaconda3\lib\site-packages\altair\utils\plugin_registry.py in __init__(self, registry, name, **options)
       23         self.options = options
       24         self.original_state = registry._get_state()
  ---&gt; 25         self.registry._enable(name, **options)
       26 
       27     def __enter__(self):
  
  ~\Anaconda3\lib\site-packages\altair\utils\plugin_registry.py in _enable(self, name, **options)
      135             except entrypoints.NoSuchEntryPoint:
      136                 if name in self.entrypoint_err_messages:
  --&gt; 137                     raise ValueError(self.entrypoint_err_messages[name])
      138                 else:
      139                     raise
  
  ValueError: 
  To use the 'notebook' renderer, you must install the vega package
  and the associated Jupyter extension.
  See https://altair-viz.github.io/getting_started/installation.html
  for more information.
  </code></pre>
  
  <p>I had found: <a href="https://stackoverflow.com/questions/52022136/getting-altair-to-work-with-jupyter-notebook">Getting Altair to work with Jupyter Notebook</a> telling me to downgrade vega to 1.3</p>
  
  <p>This errors out as:</p>
  
  <pre><code>UnsatisfiableError: The following specifications were found
  to be incompatible with the existing python installation in your environment:
  
  Specifications:
  
    - vega==1.3 -&gt; python[version='&gt;=2.7,&lt;2.8.0a0|&gt;=3.5,&lt;3.6.0a0|&gt;=3.6,&lt;3.7.0a0']
  
  Your python: python=3.7
  
  If python is on the left-most side of the chain, that's the version you've asked for.
  When python appears to the right, that indicates that the thing on the left is somehow
  not available for the python version you are constrained to. Note that conda will not
  change your python version to a different minor version unless you explicitly specify
  that.
  </code></pre>
  
  <p>I guess this makes sense as the answer to this question seems related to an older release of altair;</p>
  
  <p>Am I missing the "vega package and <strong>the associated Jupyter extension</strong>?</p>