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: _location_timestamp.rs
    path of file: ./repos/aws-sdk-rust/sdk/iot/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>Describes how to interpret an application-defined timestamp value from an MQTT message payload and the precision of that value.</p>
#[non_exhaustive]
#[derive(::std::clone::Clone, ::std::cmp::PartialEq, ::std::fmt::Debug)]
pub struct LocationTimestamp {
    /// <p>An expression that returns a long epoch time value.</p>
    pub value: ::std::string::String,
    ///
    
    pub fn build(self) -> ::std::result::Result<crate::types::LocationTimestamp, ::aws_smithy_types::error::operation::BuildError> {
        ::std::result::Result::Ok(crate::types::LocationTimestamp {
            value: self.value.ok_or_else(|| {
                ::aws_smithy_types::error::operation::BuildError::missing_field(
                    "value",
                    "value was not specified but it is required when building LocationTimestamp",
                )
            })?,
            unit: self.unit,
        })
    }