Hello,

I'm having some trouble clearing a ManyToMany field in a multipart PATCH request.

In a JSON request, I would clear my ManyToMany field, 'many_to_many_field' by PATCHing something like:

{"many_to_many_field": []}

However, in a multipart PATCH request, sending values including '[]', '', 'null', 'None', etc all yield the following error:

["Incorrect type. Expected pk value, received unicode."]

It seems that ManyRelatedField.get_value() does not recognize any of those options as special indicators of empty.