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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 abstracts(self, key, value):
 """Populate the ``abstracts`` key."""

    result = []

    source = force_single_element(value.get('9'))

    for a_value in force_list(value.get('a')):
        result.append({
            'source': source,
            'value': a_value,
        })

    return result