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: _kinesis_firehose_destination.rs
    path of file: ./repos/aws-sdk-rust/sdk/pinpointemail/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>An object that defines an Amazon Kinesis Data Firehose destination for email events. You can use Amazon Kinesis Data Firehose to stream data to other services, such as Amazon S3 and Amazon Redshift.</p>
#[non_exhaustive]
#[derive(::std::clone::Clone, ::std::cmp::PartialEq, ::std::fmt::Debug)]
pub struct KinesisFirehoseDestination {
    /// <p>The Amazon Resource Name (ARN) of the IAM role that Amazon Pinpoint uses when sending email events to the Amazon Kinesis Data Firehose stream.</p>
    pub iam_role_arn: ::std::string::String,
    /// <p>The Amazon Resource Name (ARN) of the Amazon Kinesis Data Firehose stream that Amazon Pinpoint sends email
    
    pub fn build(self) -> ::std::result::Result<crate::types::KinesisFirehoseDestination, ::aws_smithy_types::error::operation::BuildError> {
        ::std::result::Result::Ok(crate::types::KinesisFirehoseDestination {
            iam_role_arn: self.iam_role_arn.ok_or_else(|| {
                ::aws_smithy_types::error::operation::BuildError::missing_field(
                    "iam_role_arn",
                    "iam_role_arn was not specified but it is required when building KinesisFirehoseDestination",
                )
            })?,
            delivery_stream_arn: self.delivery_stream_arn.ok_or_else(|| {
                ::aws_smithy_types::error::operation::BuildError::missing_field(
                    "delivery_stream_arn",
                    "delivery_stream_arn was not specified but it is required when building KinesisFirehoseDestination",
                )
            })?,
        })
    }