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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 _represent_fold(fold_location, fold_ir_blocks):
 """Emit a LET clause corresponding to the IR blocks for a @fold scope."""

    start_let_template = u'$%(mark_name)s = %(base_location)s'
    traverse_edge_template = u'.%(direction)s("%(edge_name)s")'
    base_template = start_let_template + traverse_edge_template
    edge_direction, edge_name = fold_location.get_first_folded_edge()
    mark_name, _ = fold_location.get_location_name()
    base_location_name, _ = fold_location.base_location.get_location_name()

    validate_safe_string(mark_name)
    validate_safe_string(base_location_name)
    validate_safe_string(edge_direction)
    validate_safe_string(edge_name)

    template_data = {
        'mark_name': mark_name,
        'base_location': base_location_name,
        'direction': edge_direction,
        'edge_name': edge_name,
    }
    final_string = base_template % template_data

    for block in fold_ir_blocks:
        if isinstance(block, Filter):
            final_string += u'[' + block.predicate.to_match() + u']'
        elif isinstance(block, Traverse):
            template_data = {
                'direction': block.direction,
                'edge_name': block.edge_name,
            }
            final_string += traverse_edge_template % template_data
        elif isinstance(block, MarkLocation):
            # MarkLocation blocks inside a fold do not result in any MATCH output.
            pass
        else:
            raise AssertionError(u'Found an unexpected IR block in the folded IR blocks: '
                                 u'{} {} {}'.format(type(block), block, fold_ir_blocks))

    # Workaround for OrientDB's inconsistent return type when filtering a list.
    # https://github.com/orientechnologies/orientdb/issues/7811
    final_string += '.asList()'

    return final_string