{{{#!python
import unittest
from cStringIO import StringIO

class DNA:
    def __init__(self, title, sequence):
        self.title = title
        self.sequence = sequence

    def get_reverse_complement(self):
        base_pair = {
            'A': 'T',
            'T': 'A',
            'G': 'C',
            'C': 'G',
        }
        title = "%s reverse complement" % self.title
        new_sequence = []
        for nucleotide in self.sequence:
            new_sequence.append(base_pair[nucleotide])
        new_sequence = ''.join(reversed(new_sequence))
        return DNA(title, new_sequence)

    def write(self, cols=60):
        result = [">%s" % self.title]
        sequence = self.sequence[:]
        while sequence:
            result.append(sequence[:cols])
            sequence = sequence[cols:]
        return "\n".join(result) + '\n'
        
    @staticmethod
    def make_dna(fasta_str):
        lines = fasta_str.splitlines()
        title = lines[0][1:]
        sequence = []
        for line in lines[1:]:
            line = line.strip()
            sequence.append(line)
        sequence = ''.join(sequence)
        return DNA(title, sequence)


def FastaIterator(afile):
    lines = [afile.readline()]
    for line in afile:
        if line.startswith('>'):
            yield ''.join(lines)
            lines = [line]
        else:
            lines.append(line)
    yield ''.join(lines)


def main(input_file, output_file):
    for fasta in FastaIterator(input_file):
        dna = DNA.make_dna(fasta)
        rc_dna = dna.get_reverse_complement()
        output_file.write(rc_dna.write())
    

class DNATest(unittest.TestCase):
    def test_dna_creation(self):
        dna = DNA('test1', 'AGTCAA')
        self.assertEquals('test1', dna.title)
        self.assertEquals('AGTCAA', dna.sequence)

    def test_get_reverse_complement(self):
        dna = DNA('test1', 'AGTCAA')
        rc_dna = dna.get_reverse_complement()
        self.assertEquals('test1 reverse complement', rc_dna.title)
        self.assertEquals('TTGACT', rc_dna.sequence)

    def test_make_dna_from_fasta(self):
        input = """\
>test1
AGTC
AGTC
"""
        dna = DNA.make_dna(input)
        self.assertEquals('test1', dna.title)
        self.assertEquals('AGTCAGTC', dna.sequence)

    def test_fasta_iterator(self):
        input = StringIO("""\
>test1
AGTC
AGTC
>test2
AGTC
AGTA
>test3
AGTG
AGTC
""")
        expect1 = """\
>test1
AGTC
AGTC
"""
        expect2 = """\
>test2
AGTC
AGTA
"""
        fi = FastaIterator(input)
        self.assertEquals(expect1, fi.next())
        self.assertEquals(expect2, fi.next())

    def test_write_dna(self):
        dna = DNA('test1', 'AGTCAAGG')
        expect = """\
>test1
AGTCA
AGG
"""
        self.assertEquals(expect, dna.write(cols=5))
        

if __name__ == '__main__':
    #unittest.main()
    import sys
    main(sys.stdin, sys.stdout)
}}}