Add commonly used plots to `__init__.py`, so they can be available with just `import ax`

[sgbaird]

Here is a minimal reproducer:

import ax
print(ax.__version__)
print(dir(ax.plot))
ax.plot.marginal_effects

'0.2.3'
['__builtins__', '__cached__', '__doc__', '__file__', '__loader__', '__name__', '__package__', '__path__', '__spec__', 'base', 'color', 
'feature_importances', 'helper', 'pareto_frontier', 'pareto_utils', 'render', 'trace']
Traceback (most recent call last):
  File "<string>", line 1, in <module>
AttributeError: module 'ax.plot' has no attribute 'plot_marginal_effects'

When I "go to definition" for ax.plot it takes me to a blank __init__.py.

Running in VS Code on Windows inside a conda environment.

[sgbaird]

Digging a bit further, it turns out I can import the function directly via:

from ax.plot.marginal_effects import plot_marginal_effects
from ax.plot.diagnostic import interact_cross_validation_plotly

after which the modules are available directly:

ax.plot.marginal_effects
ax.plot.diagnostic

<module 'ax.plot.marginal_effects' from 'C:\\Users\\sterg\\Miniconda3\\envs\\crabnet-hyperparameter\\lib\\site-packages\\ax\\plot\\marginal_effects.py'>
<module 'ax.plot.diagnostic' from 'C:\\Users\\sterg\\Miniconda3\\envs\\crabnet-hyperparameter\\lib\\site-packages\\ax\\plot\\diagnostic.py'>

print(dir(ax.plot))

['__builtins__', '__cached__', '__doc__', '__file__', '__loader__', '__name__', '__package__', '__path__', '__spec__', 'base', 'color', 'diagnostic', 'feature_importances', 'helper', 'marginal_effects', 'pareto_frontier', 'pareto_utils', 'render', 'scatter', 'trace']

Not exactly what I expected, but if I can import the functions directly I don't mind doing so.

[Balandat]

Yeah just a question of what we want to surface as __all__ in the module's __init__.py. It probably makes sense to collect a few commonly used top-level functions in there.

[lena-kashtelyan]

Merging this into the wishlist for now, but it should be fairly straightforward, so we should be able to attend to this soon! In the meantime, we suggest folks just import the functions they need directly, as @sgbaird suggests above.