Scuffed script to convert markdown roleplay text into novel format

jank_convert_markdown_to_novel.py

import sys

read_file = open(sys.argv[1],"r")
roleplay_text = read_file.read()
read_file.close()

def convert_md_to_novel(text):
	novel = ""
	if '*' in text:
                parts = text.split('*')
                for part in parts:
                        if (parts.index(part) % 2) == 0 and part.strip() is not "":
                                part = part.strip()
                                if part.startswith('"') and part.endswith('"'):
                                        novel = novel + part + ' '
                                else:
                                        part = '"' + part + '"'
                                        novel = novel + part + ' '
                        elif (parts.index(part) % 2) != 0 and part.strip() is not "":
                                novel = novel + part.strip() + ' '
	else:
		novel = '"' + text.strip() + '"'
	return novel.strip()

write_file = open("output.txt","w")
final_text = ""
exclude = r"<>[]()"
lines = roleplay_text.strip().split("\n")

for line in lines:
        line = line.strip()
        if line is "":
                final_text = final_text + "\n"
        elif any(elem in line for elem in exclude):
                final_text = final_text + line + "\n"
        elif line.startswith("{{user}}:"):
                line = line.replace("{{user}}:","",1)
                final_text = final_text + "{{user}}: " + convert_md_to_novel(line) + "\n"
        elif line.startswith("{{char}}:"):
                line = line.replace("{{char}}:","",1)
                final_text = final_text + "{{char}}: " + convert_md_to_novel(line) + "\n"
        else:
                final_text = final_text + convert_md_to_novel(line) + "\n"
        
write_file.write(final_text.strip())
write_file.close()