Display code language in Rmarkdown

example.Rmd

---
title: "Display code language in Rmarkdown"
output: html_document
---

```{r setup, include=FALSE}
knitr::opts_chunk$set(eval = TRUE, include = TRUE, python.reticulate=FALSE)
```

```{r results="asis", echo=FALSE}

css <- paste0(".",
            tolower(names(knitr::knit_engines$get())),
            "::before {
            content: '",
            tolower(names(knitr::knit_engines$get())),
            "';
            display: block;
            text-align: right;
            }",
            collapse="\n")

cat(paste0("<style>", css, "</style>"))

```

```{r echo=T}
print("Hello, I'm R code")
```

```{python, engine.path = '/usr/bin/python', echo=T}
print("Hello, I'm Python code")
```

```{bash, echo=TRUE, include=TRUE}
echo "Hello, I'm Bash code"
```