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: repeated_keyword_argument.rs
    path of file: ./repos/ruff/crates/ruff_linter/src/rules/pylint/rules
    
    the code of the file until where you have to start completion: use std::hash::BuildHasherDefault;

use rustc_hash::FxHashSet;

use ruff_diagnostics::{Diagnostic, Violation};
use ruff_macros::{derive_message_formats, violation};
use ruff_python_ast::{Expr, ExprCall, ExprDict, ExprStringLiteral};
use ruff_text_size::Ranged;

use crate::checkers::ast::Checker;

/// ## What it does
/// Checks for repeated keyword arguments in function calls.
///
/// ## Why is this bad?
/// Python does not allow repeated keyword arguments in function calls. If a
/// function is called with the same keyword argument multiple times, the
/// interpreter will raise an exception.
///
/// ## Example
/// ```python
/// func(1, 2, c=3, **{"c": 4})
/// ```
///
/// ## References
/// - [Python documentation: Argument](https://docs.python.org/3/glossary.html#term-argument)
#[violation]
pub struct RepeatedKeywordArgument {
    duplicate_keyword: String,
}

impl Violation for RepeatedKeywordArgument {
    #[derive_message_formats]
    fn message(&self) -> String {
        let Self { duplicate_keyword } = self;
        format!("Repeated keyword argument: `{duplicate_keyword}`")
    }
}

pub(crate) fn repeated_keyword_argument(checker: &mut Checker, call: &ExprCall) {
    let ExprCall { arguments, .. } = call;

    let mut seen = FxHashSet::with_capacity_and_hash
    
pub(crate) fn repeated_keyword_argument(checker: &mut Checker, call: &ExprCall) {
    let ExprCall { arguments, .. } = call;

    let mut seen = FxHashSet::with_capacity_and_hasher(
        arguments.keywords.len(),
        BuildHasherDefault::default(),
    );

    for keyword in arguments.keywords.iter() {
        if let Some(id) = &keyword.arg {
            // Ex) `func(a=1, a=2)`
            if !seen.insert(id.as_str()) {
                checker.diagnostics.push(Diagnostic::new(
                    RepeatedKeywordArgument {
                        duplicate_keyword: id.to_string(),
                    },
                    keyword.range(),
                ));
            }
        } else if let Expr::Dict(ExprDict { keys, .. }) = &keyword.value {
            // Ex) `func(**{"a": 1, "a": 2})`
            for key in keys.iter().flatten() {
                if let Expr::StringLiteral(ExprStringLiteral { value, .. }) = key {
                    if !seen.insert(value.to_str()) {
                        checker.diagnostics.push(Diagnostic::new(
                            RepeatedKeywordArgument {
                                duplicate_keyword: value.to_string(),
                            },
                            key.range(),
                        ));
                    }
                }
            }
        }
    }
}