def send_mail(self, to, cc=[], bcc=[], attachfiles=[], embeddedimages_tag="graphic_embedded", embeddedimages=[]):
		"""
		Envoi d'un email à un ou plusieurs correspondants

		:param to: liste des correspondants en adresse directe
		:param cc: liste des correspondants en copie du mail
		:param bcc: liste des correspondants en copie caché du mail
		:param attachfiles: liste des fichiers à mettre en pièce jointe (chemin exacte)
		:param embeddedimages_tag: tag type <xxx> à prendre en compte dans le body HTML du mail pour intégrer des images
		:param embeddedimages: liste des images à intégrer dans le body HTML
		:return: boolean
		"""
		# vérifications d'usage
		if type(to) != list:
			raise Exception("Sendmail: error formatting adresses To (list)")

		if type(cc) != list:
			raise Exception("Sendmail: error formatting adresses Cc (list)")

		if type(bcc) != list:
			raise Exception("Sendmail: error formatting adresses Bcc (list)")

		if type(attachfiles) != list:
			raise Exception("Sendmail: error formatting attached files (list)")

		# or embeddedimages_tag.find("<") < 0 or embeddedimages_tag.find(">") < 0:
		if type(embeddedimages_tag) != str:
			raise Exception("Sendmail: error formatting tag embedded images")

		if type(embeddedimages) != list:
			raise Exception(
				"Sendmail: error formatting embedded images (list)")

		if len(to) == len(cc) == len(bcc) == 0:
			raise Exception(
				"Sendmail: error, no destinations found (to, cc, bcc)")

		# Create the root message and fill in the from, to, and subject headers
		msgRoot = MIMEMultipart('related')
		msgRoot['Subject'] = self.mail_subject
		msgRoot['From'] = "<{}>".format(
			self.mail_from) if not "<" in self.mail_from else self.mail_from
		if len(to) > 0:
			msgRoot['To'] = ", ".join(to)
		if len(cc) > 0:
			msgRoot['Cc'] = ", ".join(cc)
		if len(bcc) > 0:
			msgRoot['Bcc'] = ", ".join(bcc)
		msgRoot["Date"] = formatdate(localtime=True)
		msgRoot.preamble = 'This is a multi-part message in MIME format.'

		# Encapsulate the plain and HTML versions of the message body in an
		# 'alternative' part, so message agents can decide which they want to display.
		msgAlternative = MIMEMultipart('alternative')
		msgRoot.attach(msgAlternative)

		msgText = MIMEText(self.mail_text)
		msgAlternative.attach(msgText)

		# We reference the image in the IMG SRC attribute by the ID we give it below
		msgText = MIMEText(self.mail_html, "html", "utf-8")
		msgAlternative.attach(msgText)

		# Insertion des fichiers attachés dans le mail
		for file_pathname in attachfiles:
			try:
				# ouverture du fichier
				with open(file_pathname, 'rb') as fp:
					msgAttachment = MIMEApplication(
						fp.read(), Name=os.path.basename(file_pathname))

				msgAttachment.add_header("Content-Disposition",
										"attachment; filename=\"{}\"".format(os.path.basename(file_pathname)))
				# msgAttachment.add_header("Content-Length", os.path.getsize(file_pathname))
				msgRoot.attach(msgAttachment)

			except Exception:
				# pas de fichier valide
				pass

		# - Insertion des images dans l'email
		indice = 1
		for file_pathname in embeddedimages:
			try:
				# construction des variables
				name_embedded = "<{}{}>".format(embeddedimages_tag, indice)

				# Ouverture du fichier
				with open(file_pathname, 'rb') as fp:
					msgImage = MIMEImage(fp.read())

				# Define the image's ID as referenced above
				msgImage.add_header('Content-ID', name_embedded)
				msgRoot.attach(msgImage)

				# incrémentation
				indice += 1

			except Exception:
				# pas de fichier valide
				pass

		# Send the email (this example assumes SMTP authentication is required)
		smtp = smtplib.SMTP(
			self.smtp_host,
			self.smtp_port,
		)
		smtp.ehlo()
		# smtp.connect(smtp_host)

		# gestion du TLS
		if self.smtp_tls:
			smtp.starttls()

		# authentification
		if self.smtp_login != "":
			smtp.login(self.smtp_login, self.smtp_password)

		# Envoi du mail
		smtp.sendmail(msgRoot['From'], to + cc + bcc, msgRoot.as_string())
		smtp.quit()

		# return OK
		return True