PEP287 doesn't list available roles for interpreted text

[KubaO]

Although the Python source context reader is designed not to require explicit roles, they may be used. To classify identifiers explicitly, the role is given along with the identifier in either prefix or suffix form [...]

Only two roles are given in the example: :method: and :instance_attribute:. There is no spec for the roles anywhere (other than source code for tooling I imagine). It would really help to have a list of the available roles.

I'll gladly submit a PR if someone can point me to the "single source of truth" on those.