Suppressing MimeText Header - windows

Question

Noob, trying to automate sending infrequent personalized emails to a few dozen people, using Python and Thunderbird (I'm fine if I have to click send on each one). Unfortunately, I end up with the following extra header in the body of each message, which I would like to suppress:
Content-Type: text/plain; charset="us-ascii"
MIME-Version: 1.0
Content-Transfer-Encoding: 7bit
My code is below:
def send_email(name, email_address):
os.system("thunderbird -compose to= 'to',subject='subject',body='body'")
tbirdPath = r'c:\Program Files (x86)\Mozilla Thunderbird\thunderbird.exe'
msg = MIMEMultipart()
msg['To'] = email_address
msg['Subject'] = 'Hello Friend'
# Body of Email - part of code with display problem (in Thunderbird)
body = "Dear {}".format(name) + '\n' + '\n' + "This is the body." + '\n' + '\n' + "The End." + '\n'
composeCommand = 'format=html,to={},subject={},body={}'.format(msg['To'], msg['Subject'], MIMEText(body))
subprocess.Popen([tbirdPath, '-compose', composeCommand])
When I print to the console, I get the body I expect, but get the extra lines/header when Thunderbird populates. From the first article below, it looks like get_payload can address this (but I have no idea how). Also, I moved to MIME after having no success otherwise, and suspect that is the source of my header. (String Formatting in Python/Thunderbird). Simple answers I can implement are preferred.
Strange unwanted header when reading text file with MIMEText
Python-Parse email Body and truncate MIME headers

Answer 1

You can just truncate as many chars as necessary at the start of body to get rid of the header, i.e.
body = body[96:]
composeCommand = "format=html,to={},subject={},body='{}'".format(msg['To'], msg['Subject'], body)