GraphQL in API Playground gives error when attempting to post query filter to 10-K taken from "Cheat Sheet"
{
  FinancialFiling(filter: {AND: [{FilingDocument: {DocumentSummary: {FormType: {EQ: "10-K"}}}}, {FilingDocument: {DocumentSummary: {FilingDate: {BETWN: {FROM: "2020-01-01T00:00:00Z", TO: "2020-12-31T00:00:00Z"}}}}}]}, sort: {FilingDocument: {DocumentSummary: {FilingDate: DESC}}}, limit: 10) {
    _metadata {
      totalCount
    }
    FilingDocument {
      Identifiers {
        Dcn
      }
      DocId
      FinancialFilingId
      DocumentSummary {
        DocumentTitle
        FeedName
        FormType
        HighLevelCategory
        MidLevelCategory
        FilingDate
        SecAccessionNumber
        SizeInBytes
      }
      FilesMetaData {
        MimeType
      }
      DocumentText
    }
  }
}
