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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_data_availability(datasets_json):
 """ Given datasets in JSON format, get the data availability from it if present """

    data_availability = None
    if 'availability' in datasets_json and datasets_json.get('availability'):
        # only expect one paragraph of text
        data_availability = datasets_json.get('availability')[0].get('text')
    return data_availability