Compose email from template file

android_ci_compose_email.py

def get_email(app_name, app_version, app_url, changes, template_file_path):
    target_subject = 1
    target_body = 2
    target = 0

    subject = ""
    body = ""

    template = ""

    with(open(template_file_path)) as template_file:
        # Open template file and replace placeholders with data
        template = template_file.read().format(
            app_download_url=app_url,
            change_log=changes,
            app_name=app_name,
            app_version=app_version
        )
        
    # Iterate over each line and collect lines marked for subject/body
    for line in template.splitlines():
        if line.startswith('#'):
            if line.startswith('#subject'):
                target = target_subject
            elif line.startswith('#body'):
                target = target_body
        else:
            if target == target_subject:
                subject += line + '\n'
            elif target == target_body:
                body += line + '\n'
    
    return subject.rstrip(), body.rstrip()