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: _kms_grant_configuration.rs
    path of file: ./repos/aws-sdk-rust/sdk/accessanalyzer/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>A proposed grant configuration for a KMS key. For more information, see <a href="https://docs.aws.amazon.com/kms/latest/APIReference/API_CreateGrant.html">CreateGrant</a>.</p>
#[non_exhaustive]
#[derive(::std::clone::Clone, ::std::cmp::PartialEq, ::std::fmt
    
    pub fn build(self) -> ::std::result::Result<crate::types::KmsGrantConfiguration, ::aws_smithy_types::error::operation::BuildError> {
        ::std::result::Result::Ok(crate::types::KmsGrantConfiguration {
            operations: self.operations.ok_or_else(|| {
                ::aws_smithy_types::error::operation::BuildError::missing_field(
                    "operations",
                    "operations was not specified but it is required when building KmsGrantConfiguration",
                )
            })?,
            grantee_principal: self.grantee_principal.ok_or_else(|| {
                ::aws_smithy_types::error::operation::BuildError::missing_field(
                    "grantee_principal",
                    "grantee_principal was not specified but it is required when building KmsGrantConfiguration",
                )
            })?,
            retiring_principal: self.retiring_principal,
            constraints: self.constraints,
            issuing_account: self.issuing_account.ok_or_else(|| {
                ::aws_smithy_types::error::operation::BuildError::missing_field(
                    "issuing_account",
                    "issuing_account was not specified but it is required when building KmsGrantConfiguration",
                )
            })?,
        })
    }