Hi I am new to rust And I tried to setup a matrix rust server... and it always throws me a issue in error.rs

Question

error[E0599]: no method named `map_err` found for type parameter `Self` in the current scope
  --> src\server\error.rs:40:24
   |
34 | pub trait ResultExt<T>: Sized {
   | ----------------------------- method `map_err` not found for this type parameter
...
40 |         let res = self.map_err(|_| MatrixError::internal_err());
   |                        ^^^^^^^ method not found in `Self`
   |
   = help: items from traits can only be used if the type parameter is bounded by the trait
help: the following traits define an item `map_err`, perhaps you need to add another supertrait for one of them:
   |
34 | pub trait ResultExt<T>: Sized + ServiceFactory {
   |                               ++++++++++++++++
34 | pub trait ResultExt<T>: Sized + TryFutureExt {
   |                               ++++++++++++++
34 | pub trait ResultExt<T>: Sized + TryStreamExt {
   |                               ++++++++++++++
34 | pub trait ResultExt<T>: Sized + actix_service::Service {
   |                               ++++++++++++++++++++++++

For more information about this error, try `rustc --explain E0599`.
warning: `maelstrom` (bin "maelstrom") generated 12 warnings
error: could not compile `maelstrom` due to previous error; 12 warnings emitted

It runs into an error where it says that self.map_err is not defined

I tried to completely delete the error.rs out of the code (it didn't work)

here is the code to mess around with (oh and yes the matrix server uses actix web)

use actix_web::{http::StatusCode, Error, HttpResponse};

#[derive(Clone, Debug, serde::Serialize)]
pub struct MatrixError {
    #[serde(skip)]
    pub status: StatusCode,
    pub errcode: ErrorCode,
    pub error: String,
}

impl MatrixError {
    pub fn new(status: StatusCode, errcode: ErrorCode, error: &str) -> Self {
        MatrixError {
            status,
            errcode,
            error: error.to_string(),
        }
    }

    pub fn internal_err() -> Self {
        Self::new(
            StatusCode::INTERNAL_SERVER_ERROR,
            ErrorCode::UNKNOWN,
            "Internal server error.",
        )
    }
}
impl From<MatrixError> for Error {
    fn from(e: MatrixError) -> Self {
        HttpResponse::build(e.status).json(e).into()
    }
}

pub trait ResultExt<T>: Sized {
    fn with_codes(self, status: StatusCode, code: ErrorCode) -> Result<T, MatrixError>;
    fn unknown(self) -> Result<T, MatrixError> {
        #[cfg(debug_assertions)] // don't leak ISE info in release mode
        let res = self.with_codes(StatusCode::INTERNAL_SERVER_ERROR, ErrorCode::UNKNOWN);
        #[cfg(not(debug_assertions))]
        let res = self.map_err(|_| MatrixError::internal_err());
        res
    }
}

impl<T, E> ResultExt<T> for Result<T, E>
where
    E: std::fmt::Display,
{
    fn with_codes(self, status: StatusCode, code: ErrorCode) -> Result<T, MatrixError> {
        self.map_err(|e| MatrixError {
            status,
            errcode: code,
            error: format!("{}", e),
        })
    }
}