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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 build_marc(recid, single_keywords, composite_keywords, spires=False, author_keywords=None, acronyms=None):
 """Create xml record. :var recid: integer :var single_keywords: dictionary of kws :var composite_keywords: dictionary of kws :keyword spires: please don't use, left for historical reasons :keyword author_keywords: dictionary of extracted keywords :keyword acronyms: dictionary of extracted acronyms :return: str, marxml """

    output = ['<collection><record>\n'
              '<controlfield tag="001">%s</controlfield>' % recid]

    # no need to sort
    single_keywords = single_keywords.items()
    composite_keywords = composite_keywords.items()

    output.append(_output_marc(
        single_keywords,
        composite_keywords,
        author_keywords,
        acronyms
    ))

    output.append('</record></collection>')

    return '\n'.join(output)