How to copy to clipboard using JavaScript but also keep newline character ('\n')

Question

In my helper app I'm trying to take prototype work in Ipython and quickly turn it into a script (for when it works). I have a working clipboard function thanks to Click button copy to clipboard, on this page:

http://jsfiddle.net/codyc54321/udxp4osm/1/

While it does copy to clipboard, it comes out as a rambling string like

match = re.match(in_rgx, string)match#<_sre.SRE_Match at 0x7f90674cf3d8>match.gromatch.group match.groupdict match.groups match.group()#'In [3]: '

instead of what I see on the page:

match = re.match(in_rgx, string)

match
#<_sre.SRE_Match at 0x7f90674cf3d8>

match.gro
match.group      match.groupdict  match.groups     

match.group()
#'In [3]: '

and there is no newline separation. For some reason my fiddle isn't actually copying, but my app is, but what happens is I used a Django filter to turn my newlines (\n) into <br> tags:

<p id="clean-code">match = re.match(in_rgx, string)<br /><br />match<br />#&lt;_sre.SRE_Match at 0x7f90674cf3d8&gt;<br /><br />match.gro<br />match.group      match.groupdict  match.groups     <br /><br />match.group()<br />#&#39;In [3]: &#39;<br /></p>

and when I hit "copy to clipboard", get that string, with no br tags or newline. So if I paste into Atom, Gedit, any text editor, I get one long line which renders my page useless. I tried putting a real '\n' after each line, and as you can imagine that just added a new line. I tried putting the literal \n text, and then I get:

match = re.match(in_rgx, string)\nmatch\n#<_sre.SRE_Match at 0x7f90674cf3d8>\nmatch.group()\n#'In [3]: '\n

as one line, which makes sense. Here is my current Python with the superfluous \n:

def clean_ipython_line(code_line):
    in_rgx      = r"^In \[\d+\][:] "
    out_rgx     = r"^Out\[\d+\][:] "
    in_match    = re.match(in_rgx, code_line)
    out_match   = re.match(out_rgx, code_line)
    if in_match:
        line = code_line.replace(in_match.group(), '') + '\\n'
        return line
    elif out_match:
        line = ('#' + code_line.replace(out_match.group(), '')) + '\\n'
        return line
    else:
        return code_line
        
def clean_ipython_block(unclean_code):
    unclean_lines = unclean_code.split('\r\n')
    cleaned_lines = []
    for dirty_line in unclean_lines:
        cleaned_lines.append(clean_ipython_line(dirty_line))
    clean_block = "\r\n".join(cleaned_lines)
    print(clean_block)
    return clean_block

Is there a built in JavaScript way to copy to clipboard turning those br tags into the real newline character that will break these lines when I paste into editor?