code: def create_genome_size_dict(genome):
      # type: (str) -> Dict[str,int]
      
  
      size_file = get_genome_size_file(genome)
      size_lines = open(size_file).readlines()
  
      size_dict = {}
      for line in size_lines:
          genome, length = line.split()
          size_dict[genome] = int(length)
  
      return size_dict
docs: Creates genome size dict from string containing data.