Documented flag no-train does not seem to exist

[dumbledad]

The documentation mentions the no_train parameter, i.e. in here, but there is no mention of that flag in the code. (N.B. the flag is also inconsistently using hyphen when others use underscore).

AB#4191

[JonathanTripp]

In the class GenericConfig there is a function add_boolean_argument that has special handling for boolean arguments. If the default is True then this creates two exclusive argument options: --flag=True|False or --no-flag. The hyphen may be unusual for this project but it will be standard in argparser 3.8 onwards. See: https://docs.python.org/3/library/argparse.html where the statement

parser.add_argument('--foo', action=argparse.BooleanOptionalAction)

produces --no-foo

[ant0nsc]

by design