Rollup merge of #116133 - pouriya:refactor-bootstrap.py, r=albertlarsan68

ref(bootstrap.py): add `eprint` function

Implemented a 3-line function called `eprint` which is just like `print` but for `stderr`. So each `print(..., file=sys.stderr)` becomes `eprint(...)`.

<br/>

Testing `eprint` function:
```sh
$ cat eprint.py
```
```python
import sys

def eprint(*args, **kwargs):
	kwargs['file'] = sys.stderr
	print(*args, **kwargs)

eval('eprint({})'.format(sys.argv[1]))
```
```sh
$ python3 eprint.py '"hello"'
hello
$
```
```sh
$ python3 eprint.py '"hello"' 2>/dev/null
$
```
```sh
$ python3 eprint.py '"hello", "world", flush=True, file=sys.stdout'
hello world
$
```
```sh
$ python3 eprint.py '"hello", "world", flush=True, file=sys.stdout' 2>/dev/null
$
```

Author: matthiaskrgr