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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 confirm_top(match, data, nodegroups=None):
    '''
    Takes the data passed to a top file environment and determines if the
    data matches this minion
    '''
    matcher = 'compound'
    if not data:
        log.error('Received bad data when setting the match from the top '
                  'file')
        return False
    for item in data:
        if isinstance(item, dict):
            if 'match' in item:
                matcher = item['match']

    matchers = salt.loader.matchers(__opts__)
    funcname = matcher + '_match.match'
    if matcher == 'nodegroup':
        return matchers[funcname](match, nodegroups)
    else:
        m = matchers[funcname]
        return m(match)