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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 _export_to2marc(self, key, value):
 """Populate the ``595`` MARC field."""

    def _is_for_cds(value):
        return 'CDS' in value

    def _is_for_hal(value):
        return 'HAL' in value and value['HAL']

    def _is_not_for_hal(value):
        return 'HAL' in value and not value['HAL']

    result = []

    if _is_for_cds(value):
        result.append({'c': 'CDS'})

    if _is_for_hal(value):
        result.append({'c': 'HAL'})
    elif _is_not_for_hal(value):
        result.append({'c': 'not HAL'})

    return result