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: _coverage_map_filter.rs
    path of file: ./repos/aws-sdk-rust/sdk/inspector2/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 details of a coverage map filter.</p>
#[non_exhaustive]
#[derive(::std::clone::Clone, ::std::cmp::PartialEq, ::std::fmt::Debug)]
pub struct CoverageMapFilter {
    /// <p>The operator to compare coverage on.</p>
    pub comparison: crate::types::CoverageMapComparison,
    /// <p>The tag key associated with the coverage map filter.</p>
    pub key: ::std::string::String,
    /// <p>The tag value associated with the coverage map filter.</p>
    pub value: ::std::option::Option<::std::string::String>,
}
impl CoverageMapFilter {
    
    
    pub fn build(self) -> ::std::result::Result<crate::types::CoverageMapFilter, ::aws_smithy_types::error::operation::BuildError> {
        ::std::result::Result::Ok(crate::types::CoverageMapFilter {
            comparison: self.comparison.ok_or_else(|| {
                ::aws_smithy_types::error::operation::BuildError::missing_field(
                    "comparison",
                    "comparison was not specified but it is required when building CoverageMapFilter",
                )
            })?,
            key: self.key.ok_or_else(|| {
                ::aws_smithy_types::error::operation::BuildError::missing_field(
                    "key",
                    "key was not specified but it is required when building CoverageMapFilter",
                )
            })?,
            value: self.value,
        })
    }