# ------------------------------------------------------------------
# File name: for.py
#
# for item in items:
#      statements

# Python’s for statement iterates over the items of any sequence
# (a list or a string), in the order that they appear in the sequence.
#
# Code below prints out all codons starting with T.
#
# Version: 2.1
# Authors: H. Kocak and B. Koc
#          University of Miami and Stetson University
# References:
# https://docs.python.org/3/tutorial/controlflow.html#for-statements
# https://docs.python.org/3/reference/compound_stmts.html#for
# https://en.wikipedia.org/wiki/DNA_codon_table
# ------------------------------------------------------------------

# Save nucleotide bases in a list
bases = ['T', 'C', 'A', 'G']

# As a warmup, print the list of bases
for base in bases:
    print(base)

print('Codons starting with T:')

for second_base in bases:
    print('Codons starting with T'+second_base)
    for third_base in bases:
        print('T'+second_base+third_base)