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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 map_tag_to_subfield(tag_type, line, cur_misc_txt, dest):
 """Create a new reference element"""

    closing_tag = '</cds.%s>' % tag_type
    # extract the institutional report-number from the line:
    idx_closing_tag = line.find(closing_tag)
    # Sanity check - did we find a closing tag?
    if idx_closing_tag == -1:
        # no closing </cds.TAG> tag found - strip the opening tag and move past this
        # recognised reportnumber as it is unreliable:
        identified_citation_element = None
        line = line[len('<cds.%s>' % tag_type):]
    else:
        tag_content = line[:idx_closing_tag]
        identified_citation_element = {'type': tag_type,
                                       'misc_txt': cur_misc_txt,
                                       dest: tag_content}
        ending_tag_pos = idx_closing_tag + len(closing_tag)
        line = line[ending_tag_pos:]
        cur_misc_txt = u""

    return identified_citation_element, line, cur_misc_txt