strain_id	description	flag	length
NC_017906.1	Escherichia coli Xuzhou21, complete sequence	genbank	5386223
NC_017907.1	Escherichia coli Xuzhou21 plasmid pO157, complete sequence	genbank	92728
NC_017903.1	Escherichia coli Xuzhou21 plasmid pO157_Sal, complete sequence	genbank	37785
