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:       hg16:chr2:1,000,000-1,000,100       mm4:chr3:2,000-3,000