Further improve the Python API for the package to complement the CLI

We are currently at:

# should be easy to clean these up at some point, not important
from nhssynth.modules.dataloader.metatransformer import MetaTransformer
from nhssynth.modules.model.models import DPVAE

import pandas as pd

data = pd.read_csv("data/support.csv")
# This step is technically optional, we could instead do MetaTransformer(df) but then it will auto-generate metadata (which is imperfect)
mt = MetaTransformer.from_path(data, "data/support_metadata.yaml")
prepared_data = mt.apply()

# It makes far more sense (in my opinion) to instantiate the model with the data, as this determines the structure of the instantiated object + the thing we want to save etc. (I say this because other packages sometimes would put the data in when you decide to train
model = DPVAE(prepared_data, mt)
results = model.train()

synthetic_data = model.generate(1000)

nhsengland / NHSSynth

Further improve the Python API for the package to complement the CLI #73