svg generator script i hacked for automation of email header generation

header-generator.py

from xml.sax.saxutils import escape as xmlescape
import subprocess
import os
import re
import sys

def get_valid_filename(s):
    """
    Returns the given string converted to a string that can be used for a clean
    filename. Specifically, leading and trailing spaces are removed; other
    spaces are converted to underscores; and anything that is not a unicode
    alphanumeric, dash, underscore, or dot, is removed.
    >>> get_valid_filename("john's portrait in 2004.jpg")
    'johns_portrait_in_2004.jpg'
    """
    s = s.strip().replace(' ', '_')
    return re.sub(r'(?u)[^-\w.]', '', s)

template = "20160209_gradar_header_vorlage.svg"
key = "$subject"
replacements = [
    "welcome",
    "willkommen",
    "bienvenido/a",
    "thank you",
    "vielen dank",
    "gracias",
    "reminder",
    "erinnerung",
    "recordatorio",
    "last reminder",
    "letzte erinnerung",
    "último recordatorio",
    "your impression",
    "erster eindruck",
    "primera impresión",
    "your feedback",
    "erstes feedback",
    "su opinión",
    "missing you",
    "sie fehlen uns",
    "nos hace falta",
    "please confirm",
    "bitte bestätigen",
    "confirme su cuenta"
]
genfile = ".gen.svg"
outdir = "output"

if not os.path.exists(outdir):
    os.makedirs(outdir)

if __name__ == '__main__':
    print("opening template")
    with open(template, 'r') as fp:
        svgstr = fp.read()

        for index, value in enumerate(replacements):
            print(value)
            svggen = svgstr.replace(key, xmlescape(str(value)))

            with open(genfile, 'w') as genfp:
                genfp.write(svggen)
                genfp.close()

                errorReturn = subprocess.check_output(
                    'inkscape --export-png={0}/{1:02d}_{2}.png {3} >/dev/null 2>&1'.
                        format(outdir, index, get_valid_filename(value), genfile),
                        shell=True, universal_newlines=True)

                if errorReturn != '':
                    print("inkscape exitted with error\n" + errorReturn)
                    sys.exit(42)