You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: single_attr_body.go
    path of file: ./repos/terraform/internal/configs/hcl2shim
    
    the code of the file until where you have to start completion: // Copyright (c) HashiCorp, Inc.
// SPDX-License-Identifier: BUSL-1.1

package hcl2shim

import (
    
func (b SingleAttrBody) Content(schema *hcl2.BodySchema) (*hcl2.BodyContent, hcl2.Diagnostics) {
	content, all, diags := b.content(schema)
	if !all {
		// This should never happen because this body implementation should only
		// be used by code that is aware that it's using a single-attr body.
		diags = append(diags, &hcl2.Diagnostic{
			Severity: hcl2.DiagError,
			Summary:  "Invalid attribute",
			Detail:   fmt.Sprintf("The correct attribute name is %q.", b.Name),
			Subject:  b.Expr.Range().Ptr(),
		})
	}
	return content, diags
}