Update condition for email sending

courses/models.py

@@ -805,15 +805,18 @@ class ProfessorMessage(models.Model):
 
             subject_en = Template(et.subject).render(Context({'subject': self.subject_en}))
             message_en = Template(et.template).render(Context({'message': self.message_en}))
-            self.send_emails(bcc_en, message_en, subject_en, email_batch_size)
+            if subject_en and message_en:
+                self.send_emails(bcc_en, message_en, subject_en, email_batch_size)
 
             subject_es = Template(et.subject).render(Context({'subject': self.subject_es}))
             message_es = Template(et.template).render(Context({'message': self.message_es}))
-            self.send_emails(bcc_es, message_es, subject_es, email_batch_size)
+            if subject_es and message_es:
+                self.send_emails(bcc_es, message_es, subject_es, email_batch_size)
 
             subject_pt_br = Template(et.subject).render(Context({'subject': self.subject_pt_br}))
             message_pt_br = Template(et.template).render(Context({'message': self.message_pt_br}))
-            self.send_emails(bcc_pt_br, message_pt_br, subject_pt_br, email_batch_size)
+            if subject_pt_br and message_pt_br:
+                self.send_emails(bcc_pt_br, message_pt_br, subject_pt_br, email_batch_size)
         else:
             bcc = [u.email for u in self.users.all() if u.is_active and re.match(r"(^[a-zA-Z0-9_.+-]+@[a-zA-Z0-9-]+\.[a-zA-Z0-9-.]+$)", u.email)]
             subject = Template(et.subject).render(Context({'subject': self.subject}))