def add_uid(uid)
      raise ArgumentError, "Invalid argument 'uid'. Expected UID, got #{uid.class}" unless uid.is_a?(UID)
      # We store the uids in a hash with uid-value as key and the uid instance as value:
      @uids[uid.value] = uid
    end
def add_uid(uid)
      raise ArgumentError, "Invalid argument 'uid'. Expected UID, got #{uid.class}" unless uid.is_a?(UID)
      # We store the uids in a hash with uid-value as key and the uid instance as value:
      @uids[uid.value] = uid
    end
Adds a custom uid (e.g. SOP Class, Transfer Syntax) to the ruby-dicom uid dictionary.

 @param [UID] uid the custom uid instance to be added