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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 _get_table_start(self):
 """ prefill the columns we need for all tables """

        if self.documentation:
            standardized_table_start = {
                'object_id': {
                    'value': self.object_id,
                    'ordering': -1,
                    'line_number': 'NA',
                    'description': 'IRS-assigned object id',
                    'db_type': 'String(18)'
                },
                'ein': {
                    'value': self.ein,
                    'ordering': -2,
                    'line_number': 'NA',
                    'description': 'IRS employer id number',
                    'db_type': 'String(9)'
                }
            }
            if self.documentId:
                standardized_table_start['documentId'] = {
                    'value': self.documentId,
                    'description': 'Document ID',
                    'ordering': 0
                }
        else:
            standardized_table_start = {
                'object_id': self.object_id,
                'ein': self.ein
            }
            if self.documentId:
                standardized_table_start['documentId'] = self.documentId

        return standardized_table_start