Type Error bug in azure-sdk-for-python

There seems to be an issue creating a field of type Collection(EdmSingle) in azure-search-documents==1.15.1 This could be a bug in azure-sdk-for-python

SearchFieldDataType.Collection(SearchFieldDataType.Single) -> Edm.String

(python program)
fields = [
SearchableField(name="titleVector", type=SearchFieldDataType.Collection(SearchFieldDataType.Single), searchable=True, vector_search_dimensions=3072, vector_search_profile_name="myHnswProfile"),
]
↓
(JSON)
{
"name": "titleVector",
"type": "Edm.String",
:
}

Start with the Python program shown in the issue and inspect how SearchFieldDataType.Collection(SearchFieldDataType.Single) is serialized in azure-search-documents==1.15.1. Compare the generated JSON with the expected EdmSingle collection type. Done means the field no longer serializes as Edm.String, with the behavior verified against the reported example.

Written by the indexing model from the issue text.