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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def abook_file(vcard, bookfile):
 """Write a new Abook file with the given vcards"""

        book = ConfigParser(default_section='format')

        book['format'] = {}
        book['format']['program'] = 'abook'
        book['format']['version'] = '0.6.1'

        for (i, card) in enumerate(readComponents(vcard.read())):
            Abook.to_abook(card, str(i), book, bookfile)
        with open(bookfile, 'w') as fp:
            book.write(fp, False)