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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 _get_org(aff):
 """Auxiliary function to extract org information from affiliation for authorgroup. """

    try:
        org = aff['organization']
        if not isinstance(org, str):
            try:
                org = org['$']
            except TypeError:  # Multiple names given
                org = ', '.join([d['$'] for d in org if d])
    except KeyError:  # Author group w/o affiliation
        org = None
    return org