text: import DNAStrand from './dna-strand';
  
  test('case #', () => {
    expect(DNAStrand('AAAA')).toBe('TTTT');
  });
  
  test('case #', () => {
    expect(DNAStrand('ATTGC')).toBe('TAACG');
  });
  
  test('case #', () => {
    expect(DNAStrand('GTAT')).toBe('CATA');
  });
  