This utility automatically fetches multiple sequences from genome assemblies.

Please use the following format for the sequences specification:
      <freeze>:<chromosome>:<from>-<to>
      <freeze>:<chromosome>:<from>-<to>
      . . .
      <freeze>:<chromosome>:<from>-<to>

For example:
      hg18:chr2:1,000,000-1,000,100
      mm9:chr3:11002000-11004100