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: _dashboard_summary.rs
    path of file: ./repos/aws-sdk-rust/sdk/iotsitewise/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>Contains a dashboard summary.</p>
#[non_exhaustive]
#[derive(::std::clone::Clone, ::std::cmp::PartialEq, ::std::fmt::Debug)]
pub struct DashboardSummary {
    /// <p>The ID of the dashboard.</p>
    pub id: ::std::string::String,
    /// <p>The name of the dashboard</p>
    pub name: ::std::string::String,
    /// <p>The dashboard's description.</p>
    pub description: ::std::option::Option<::std::string::String>,
    /// <p>The date the dashboard was created, in Unix epoch time.</p>
    pub creation_date
    
    pub fn build(self) -> ::std::result::Result<crate::types::DashboardSummary, ::aws_smithy_types::error::operation::BuildError> {
        ::std::result::Result::Ok(crate::types::DashboardSummary {
            id: self.id.ok_or_else(|| {
                ::aws_smithy_types::error::operation::BuildError::missing_field(
                    "id",
                    "id was not specified but it is required when building DashboardSummary",
                )
            })?,
            name: self.name.ok_or_else(|| {
                ::aws_smithy_types::error::operation::BuildError::missing_field(
                    "name",
                    "name was not specified but it is required when building DashboardSummary",
                )
            })?,
            description: self.description,
            creation_date: self.creation_date,
            last_update_date: self.last_update_date,
        })
    }