How to define a slot whose values are comparable to a dictionary in Python?

[candleindark]

Is it possible and how to define a slot whose values are comparable to a dictionary in Python?

For example, how to express the digest field in the following simplified model taken from the Dandi project.

from enum import Enum

from pydantic import BaseModel


class DigestType(Enum):
    """An enumeration of checksum types"""

    #: MD5 checksum
    md5 = "dandi:md5"

    #: SHA1 checksum
    sha1 = "dandi:sha1"

    #: SHA2-256 checksum
    sha2_256 = "dandi:sha2-256"

    #: SHA3-256 checksum
    sha3_256 = "dandi:sha3-256"

    #: BLAKE2B-256 checksum
    blake2b_256 = "dandi:blake2b-256"

    #: BLAKE3-256 checksum
    blake3 = "dandi:blake3"

    #: S3-style ETag
    dandi_etag = "dandi:dandi-etag"

    #: DANDI Zarr checksum
    dandi_zarr_checksum = "dandi:dandi-zarr-checksum"


class BareAsset(BaseModel):
    # A map of digests to their values
    digest: dict[DigestType, str]

[cmungall]

See https://linkml.io/linkml/schemas/inlining.html#inlining-as-simple-dictionaries

But this is still a bit verbose at the object level. I think this is something we want to prioritize moving forward

[candleindark]

bare_asset.yaml

id: https://w3id.org/linkml/examples/bareasset
name: bareasset
prefixes:
  linkml: https://w3id.org/linkml/
  bareasset: https://w3id.org/linkml/examples/bareasset
imports:
  - linkml:types
default_range: string
default_prefix: bareasset

enums:
  DigestType:
    permissible_values:
      md5:
      sha1:
      sha2_256:
      sha3_256:
      blake2b_256:
      blake3:
      dandi_etag:
      dandi_zarr_checksum:

classes:
  Digest:
    attributes:
      type:
        range: DigestType
        key: true
      value:
        range: string
  BareAsset:
    attributes:
      digest:
        range: Digest
        multivalued: true
        inlined: true
        inlined_as_list: false

1. Do you mean that, currently, one has to bundle the key and value in a class definition as I did in the Digest class in the example above to achieve the goal mentioned?
2. Is there any limitation on the range of the key/identifier slot of the newly defined class, i.e. can the range of the slot be any type?
3. What are the difference between the key meta slot and the identifier meta slot.
4. I think there is bug in this feature https://linkml.io/linkml/schemas/inlining.html#inlining-as-simple-dictionaries if my understanding is correct.
   1. Given data.yaml

      - digest:
          md5: "md5 value"
          sha1: "sha1 value"
      - digest:
          foo: "foo value"
          sha3_256: "sha3_256 value"

   2. Run linkml-validate -C BareAsset -s bare_asset.yaml data.yaml produces no error even though "foo" is an invalid value for the type slot of Digest.