code: def nt2aa(ntseq):
      
      nt2num = {'A': 0, 'C': 1, 'G': 2, 'T': 3, 'a': 0, 'c': 1, 'g': 2, 't': 3}
      aa_dict ='KQE*TPASRRG*ILVLNHDYTPASSRGCILVFKQE*TPASRRGWMLVLNHDYTPASSRGCILVF'
      
      return ''.join([aa_dict[nt2num[ntseq[i]] + 4*nt2num[ntseq[i+1]] + 16*nt2num[ntseq[i+2]]] for i in range(0, len(ntseq), 3) if i+2 < len(ntseq)])
docs: Translate a nucleotide sequence into an amino acid sequence.
  
      Parameters
      ----------
      ntseq : str
          Nucleotide sequence composed of A, C, G, or T (uppercase or lowercase)
  
      Returns
      -------
      aaseq : str
          Amino acid sequence
      
      Example
      --------
      >>> nt2aa('TGTGCCTGGAGTGTAGCTCCGGACAGGGGTGGCTACACCTTC')
      'CAWSVAPDRGGYTF'