undeclared field: 'mimes' for type mimetypes.MimeDB

[ingo]

The code below results in the error: 
    
    
    Error: undeclared field: 'mimes' for type mimetypes.MimeDB [declared in ...]
    found 'mimes' of kind 'const'
    
    Run

I do not understand why and see no way out.
    
    
    import mimetypes
    from strutils import toLowerAscii
    
    var mime = newMimetypes()
    mime.register("ape", "audio/x-ape")
    
    func getExtensions(mimedb: MimeDB, mimetype: string, default = 
"undefined"): seq[string] =
      let mimeLowered = mimetype.toLowerAscii()
      for e, m in mimedb.mimes:                               #<--- errors here
        if mimelowerer.find("audio") > -1:
          echo e
          result.add(e)
    
    #Error: undeclared field: 'mimes' for type mimetypes.MimeDB [declared in 
...]
    #  found 'mimes' of kind 'const'
    
    
    Run

TIA