b

# string que irá armazenar a cadeia de bases
t = 'CCGCTACACGCGTACCAACTCCGCCTTGTACCGCCTCTGAGACTTTCCACGGTATCCCCGACTGTCGACTATAAGACGTTGTTAACAATCCATTTCTTATACTATCACTTCACACTGTTCTAATAGCAAAGTCGTCCGAGTGTGCATGGAGAGCTACTTTTCGCAGTCCACGGGCGCTATCATTAGGAGCGGCGTATAATGGTCGGACAGAGGCCAGCGTCAGCCCCAGTCCACTAGCCCCGGAGAACGTTTGTACGGAGACGCCCATTGGAGCATTAGCATGGGCCGTACGACACGTAATAGGAGCAAGGCGATTCTCGTGTTGCTAACTCCGGACCAAGTGAGAACTACTTCAAAAAATGTAGTCTCGTAGGAGTCAGAACAAGCAAACTCGAAAGGCTACTCTGTGCCGAGCATACGAGATCTATTCTTAGGCACAAGCTTGAAAAGGGGATTAATGCAGTAGAGTGATGTCGAGAACCAACCTGGGCGGCACTAGACCTAAGCAGGTAACAGTGGACATCAACGTGGATTAGCGGACGAATTTTTACTATTGGGAATAGCAAGGATTAAGGGGAGAACGTTCAAACCACATTTCCGGCAGCCTCAGTGTAGGCCCAGAGCCACTCCCAGAGACCCGCTCAGTGCACAGTTCGTAATTGGAGAATAGGCAGTGTCATAACTTATCATGATAGCCTCTCTAACTGTACGACTCATAATGTGTAAATGACCTCAGTAGTGCCGGTAGCGACCTGATGCGTCCAGATTATACCCGCTTGTAGGCTCAAGCTTATTTGACTACGGTCTCTGTCATAGGACAGTCAGTAGGGACAATACGCTTTATATCTGGGAACGCTGCATAAACGCTCCTTCCAAGCTACCCGAACAATCACCGCTCAGAAACCTGAGAACCAACCTCATTGATTTAATTAACCCCCAAGAACGCCCAGACACTTTTGATGCGAAAGGAG'

# a variável irá receber a string susbstituindo todos os elementos
# 'T' por 'U'
t = t.replace('T', 'U')

print(t)