new_contents: # -*- coding: utf-8 -*-
  
  """
  Copyright [2009-2018] EMBL-European Bioinformatics Institute
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
  http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
  """
  
  import six
  
  try:
      import enum
  except ImportError:
      from enum32 import enum
  
  
  @enum.unique
  class Database(enum.Enum):
      """
      This is an enum that is used to represent the databases that RNAcentral
      knows about.
      """
  
      dictybase      = 0
      ena            = 1
      ensembl        = 2
      ensembl_plants = 3
      flybase        = 4
      gencode        = 5
      greengenes     = 5
      gtrnadb        = 6
      hgnc           = 7
      lncbase        = 8
      lncbook        = 9
      lncipedia      = 10
      lncrnadb       = 11
      mgi            = 12
      mirbase        = 13
      modomics       = 14
      noncode        = 15
      pdbe           = 16
      pombase        = 17
      rdp            = 18
      refseq         = 19
      rfam           = 20
      rgd            = 21
      sgd            = 22
      silva          = 23
      snopy          = 24
      srpdb          = 25
      tair           = 26
      tarbase        = 27
      tmrna_website  = 28
      vega           = 29
      wormbase       = 30
      zwd            = 31
  
      @classmethod 
      def build(cls, name):
          if isinstance(value, cls):
              return value
          attribute = name.lower().replace(' ', '_')
          if hasattr(cls, attribute):
              return getattr(cls, attribute)
          if name == 'pdb':
              return cls.pdbe
          if name == 'tmrna-website':
              return cls.tmrna_website
          if name == 'snopydb':
              return cls.snopy
          raise ValueError("Unknown database name %s" % name)
  
      def normalized(self):
          return self.name.upper()
  
      def public_name(self):
          if self is Database.pdbe:
              return 'PDB'
          return self.name.upper()
  
subject: Add an enum to represent databases