Automating the sending of a matplotlib chart in outlook (python)

I have created a chart in matplotlib which I would like to send somewhat automatically.

I've converted the chart to png and then saved it as a variable as follows:

chart = io.BytesIO()
plt.savefig(chart, format='png')
chart.seek(0)
im = Image.open(chart)

def get_plot():
    return im

It doesn't need to be in a png format to complete the task, I just thought saving it in that format would be the best way to store it.

I have then set up auto-generated email (today is a variable that holds the day's date):

def Emailer(text, subject, recipient):
     outlook = win32com.client.Dispatch('outlook.application')
     mail = outlook.CreateItem(0)
     mail.To = recipient
     mail.Subject = subject
     mail.HtmlBody = text
     mail.Display(True)
    
    MailSubject= "Auto test mail at "+today
    MailInput=im
    MailAdress='recipient@guyIwanttosendemailsto.com'
    
    Emailer(MailInput, MailSubject, MailAdress )

Unfortunately when I run the code, I get an error message saying:

TypeError: Objects of type 'PngImageFile' can not be converted to a COM VARIANT (but obtaining the buffer() of this object could)

If I didn't have the 'im' variable in the 'MailInput' the email works exactly as intended. I was wondering if any of you had some advice on how to finish this task?