[scripts][s]: convert constituents.sh shell code into python as part of constituents.py.

Had encountered an error due to new line in a field (caused by addition of 20th century fox with a comma in its name) so thought worth converting to make this more robust.
[data/constituents][s]: latest update with 4 additions/removals (other changes due to slight change in how we sort).
[data/financials][s]: regular update.