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: _run_command_parameters.rs
    path of file: ./repos/aws-sdk-rust/sdk/cloudwatchevents/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>This parameter contains the criteria (either InstanceIds or a tag) used to specify which EC2 instances are to be sent the command.</p>
#[non_exhaustive]
#[derive(::std::clone::Clone, ::std::cmp::PartialEq, ::std::fmt::Debug)]
pub struct RunCommandParameters {
    /// <p>Currently, we support including only one RunC
    
    pub fn build(self) -> ::std::result::Result<crate::types::RunCommandParameters, ::aws_smithy_types::error::operation::BuildError> {
        ::std::result::Result::Ok(crate::types::RunCommandParameters {
            run_command_targets: self.run_command_targets.ok_or_else(|| {
                ::aws_smithy_types::error::operation::BuildError::missing_field(
                    "run_command_targets",
                    "run_command_targets was not specified but it is required when building RunCommandParameters",
                )
            })?,
        })
    }