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: _ssm_document.rs
    path of file: ./repos/aws-sdk-rust/sdk/mgn/src/types
    
    the code of the file until where you have to start completion: // Code generated by software.amazon.smithy.rust.codegen.smithy-rs. DO NOT EDIT.

/// <p>AWS Systems Manager Document.</p>
#[non_exhaustive]
#[derive(::std::clone::Clone, ::std::cmp::PartialEq, ::std::fmt::Debug)]
pub struct SsmDocument {
    /// <p>User-friendly name for the AWS Systems Manager Document.</p>
    pub action_name: ::std::string::String,
    /// <p>AWS Systems Manager Document name or full ARN.</p>
    pub ssm_document_name: ::std::string::String,
    /// <p>AWS Systems Manager Document timeout seconds.</p>
    pub timeout_seconds: ::std::option::Option<i32>,
    /// <p>If true, Cutover will not be enabled if the document has failed.</p>
    pub must_succeed_for_cutover: ::std::option::Option<bool>,
    /// <p>AWS Systems Manager Document parameters.</p>
    pub parameters:
        ::std::option::Opti
    
    pub fn build(self) -> ::std::result::Result<crate::types::SsmDocument, ::aws_smithy_types::error::operation::BuildError> {
        ::std::result::Result::Ok(crate::types::SsmDocument {
            action_name: self.action_name.ok_or_else(|| {
                ::aws_smithy_types::error::operation::BuildError::missing_field(
                    "action_name",
                    "action_name was not specified but it is required when building SsmDocument",
                )
            })?,
            ssm_document_name: self.ssm_document_name.ok_or_else(|| {
                ::aws_smithy_types::error::operation::BuildError::missing_field(
                    "ssm_document_name",
                    "ssm_document_name was not specified but it is required when building SsmDocument",
                )
            })?,
            timeout_seconds: self.timeout_seconds,
            must_succeed_for_cutover: self.must_succeed_for_cutover,
            parameters: self.parameters,
            external_parameters: self.external_parameters,
        })
    }