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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 correspondence(soup):
 """ Find the corresp tags included in author-notes for primary correspondence """

    correspondence = []

    author_notes_nodes = raw_parser.author_notes(soup)

    if author_notes_nodes:
        corresp_nodes = raw_parser.corresp(author_notes_nodes)
        for tag in corresp_nodes:
            correspondence.append(tag.text)

    return correspondence