code: public static int countAT(Sequence<NucleotideCompound> sequence) {
  		CompoundSet<NucleotideCompound> cs = sequence.getCompoundSet();
  		NucleotideCompound A = cs.getCompoundForString("A");
  		NucleotideCompound T = cs.getCompoundForString("T");
  		NucleotideCompound a = cs.getCompoundForString("a");
  		NucleotideCompound t = cs.getCompoundForString("t");
  		return countCompounds(sequence, A, T, a, t);
  	}
docs: Returns the count of AT in the given sequence
  
  @param sequence The {@link NucleotideCompound} {@link Sequence} to perform
  the AT analysis on
  @return The number of AT compounds in the sequence