Write to request references from yaml list of referees

writeemails.py

import smtplib
import yaml

from email.message import EmailMessage
from email.utils import make_msgid
from email.mime.base import MIMEBase
from email import encoders
from email.mime.multipart import MIMEMultipart
from email.mime.text import MIMEText
from email.mime.application import MIMEApplication

smtp_server = 'smtp.local.com'
smtp_port = 587
smtp_username = '[email protected]'
smtp_password = 'xxxx'
"""
Yaml is something like:
Joan Smith:
    - Jones: [email protected]
    - Piper: [email protected]
Fred Cohen:
    - Frances: [email protected]
    - Piper: [email protected]
"""

with open('References.yaml') as fin:
    references = yaml.safe_load(fin)
    print(references)
for app in references:
    print(app)
    for ref in references[app]:
        for reff in ref:
            print(reff)
            print(ref[reff])
            reference = reff
            email = ref[reff]
            applicant = app
            from_email = '[email protected]'
            to_email = email
            subject = f'Subject: PDF reference for {applicant}'
            body = f"""
Dear Dr. {reference}

We received an application from {applicant} for a postdoctoral fellowship on "Ocean sub-mesoscales using in-situ data, satellites, and simulations" with our group at UVic and DFO.  The job advertisement is attached below.  They are on our long list of potential applicants and we were wondering if you had a few minutes to give us an idea of their suitability for the position.  We are particularly interested in the level of independence and originality they showed in their research with you, and if you feel they would be successful in the role. We appreciate that you probably have lots of other commitments, so an informal email in response is fine, or we are happy to have a quick call if that is easier.

Thanks,

Jody Klymak,
"""
            msg = MIMEMultipart()
            msg['From'] = from_email
            msg['To'] = to_email
            msg['Subject'] = subject
            msg['Cc'] = '[email protected], [email protected]'
            msg.attach(MIMEText(body, 'plain'))
            pdf_filename = 'PDF_CSA_2024_Ad.pdf'
            with open(pdf_filename, 'rb') as f:
                pdf_attachment = MIMEApplication(f.read(), _subtype='pdf')
                pdf_attachment.add_header('Content-Disposition', 'attachment',      filename=pdf_filename)
                msg.attach(pdf_attachment)
            try:
                with smtplib.SMTP(smtp_server, smtp_port) as server:
                    server.starttls()  # Upgrade the connection to secure
                    server.login(smtp_username, smtp_password)
                    server.sendmail(from_email, to_email, msg.as_string())
                    print('Email sent successfully')
            except Exception as e:
                print(f'Failed to send email: {e}')