# ShowNested.py
""" Practice with Nested Loops
"""

def AminoAcids(alpha):
    """
    
    PreC: alpha is a nonempty string.
    """
    n = len(alpha)
    for i in range(n):
         for j in range(n):
               for k in range(n):
                  w = alpha[i]+alpha[j]+alpha[k]
                  print w

if __name__ == '__main__':
    AminoAcids('AGCT')