Send email in Python 3

mail.py

import smtplib
import traceback
from email import encoders
from email.mime.base import MIMEBase
from email.mime.multipart import MIMEMultipart
from email.mime.text import MIMEText
from email.utils import COMMASPACE, formataddr, formatdate, parseaddr
from pathlib import Path
from typing import List


class MailClient:
    def __init__(
        self,
        host: str,
        port: int,
        use_tls: bool,
        user: str,
        password: str,
        debug=False,
    ):
        self._host = host
        self._port = port
        self._use_tls = use_tls
        self._user = user
        self._password = password
        self._debug = debug
        self._connection = None

    @staticmethod
    def format_addr(addr: str) -> str:
        return formataddr(parseaddr(addr))

    def _send(self, from_addr: str, to_addrs: str, msg: str) -> None:
        try:
            self._connection = smtplib.SMTP(host=self._host, port=self._port)
            self._connection.set_debuglevel(1 if self._debug else 0)
            if self._use_tls:
                self._connection.starttls()
            if self._user and self._password:
                self._connection.login(self._user, self._password)
            self._connection.sendmail(from_addr, to_addrs, msg)
        except:
            print(traceback.format_exc())
        finally:
            self._connection.quit()

    def sendmail(
        self,
        from_addr: str,
        to_addrs: List[str],
        reply_to_addr: str = None,
        cc_addrs: List[str] = None,
        bcc_addrs: List[str] = None,
        subject: str = None,
        plain_text_body: str = None,
        html_body: str = None,
        attachments: List[str] = None,
    ):
        cleaned_from_addr = self.format_addr(from_addr)
        cleaned_to_addrs = COMMASPACE.join(
            [self.format_addr(addr) for addr in to_addrs]
        )

        message = MIMEMultipart("alternative")
        message["Date"] = formatdate()
        message["From"] = cleaned_from_addr
        message["To"] = cleaned_to_addrs
        if reply_to_addr:
            message.add_header("Reply-To", self.format_addr(reply_to_addr))
        if cc_addrs:
            message["Cc"] = COMMASPACE.join(
                [self.format_addr(addr) for addr in cc_addrs]
            )
        if bcc_addrs:
            message["Bcc"] = COMMASPACE.join(
                [self.format_addr(addr) for addr in bcc_addrs]
            )
        if subject:
            message["Subject"] = subject
        if plain_text_body:
            message.attach(MIMEText(plain_text_body, "plain"))
        if html_body:
            message.attach(MIMEText(html_body, "html"))
        if attachments:
            for item in attachments:
                with open(item, "rb") as attachment:
                    part = MIMEBase("application", "octet-stream")
                    part.set_payload(attachment.read())
                encoders.encode_base64(part)
                part.add_header(
                    "Content-Disposition",
                    'attachment; filename="{}"'.format(Path(item).name),
                )
                message.attach(part)
        self._send(cleaned_from_addr, cleaned_to_addrs, message.as_string())