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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 str_presenter(dmpr, data):
 """Return correct str_presenter to write multiple lines to a yaml field. Source: http://stackoverflow.com/a/33300001 """

    if is_multiline(data):
        return dmpr.represent_scalar('tag:yaml.org,2002:str', data, style='|')
    return dmpr.represent_scalar('tag:yaml.org,2002:str', data)