Add translate region tags [(#1488)](GoogleCloudPlatform/python-docs-s…

…amples#1488)

* Add region tags

* Added end region tags

* Linting errors fixed

samples/snippets/snippets.py

@@ -28,6 +28,7 @@
 
 
 def detect_language(text):
+    # [START translate_detect_language]
     """Detects the text's language."""
     translate_client = translate.Client()
 
@@ -38,19 +39,23 @@ def detect_language(text):
     print('Text: {}'.format(text))
     print('Confidence: {}'.format(result['confidence']))
     print('Language: {}'.format(result['language']))
+    # [END translate_detect_language]
 
 
 def list_languages():
+    # [START translate_list_codes]
     """Lists all available languages."""
     translate_client = translate.Client()
 
     results = translate_client.get_languages()
 
     for language in results:
         print(u'{name} ({language})'.format(**language))
+    # [END translate_list_codes]
 
 
 def list_languages_with_target(target):
+    # [START translate_list_language_names]
     """Lists all available languages and localizes them to the target language.
 
     Target must be an ISO 639-1 language code.
@@ -62,9 +67,11 @@ def list_languages_with_target(target):
 
     for language in results:
         print(u'{name} ({language})'.format(**language))
+    # [END translate_list_language_names]
 
 
 def translate_text_with_model(target, text, model=translate.NMT):
+    # [START translate_text_with_model]
     """Translates text into the target language.
 
     Make sure your project is whitelisted.
@@ -86,9 +93,11 @@ def translate_text_with_model(target, text, model=translate.NMT):
     print(u'Translation: {}'.format(result['translatedText']))
     print(u'Detected source language: {}'.format(
         result['detectedSourceLanguage']))
+    # [END translate_text_with_model]
 
 
 def translate_text(target, text):
+    # [START translate_translate_text]
     """Translates text into the target language.
 
     Target must be an ISO 639-1 language code.
@@ -108,6 +117,7 @@ def translate_text(target, text):
     print(u'Translation: {}'.format(result['translatedText']))
     print(u'Detected source language: {}'.format(
         result['detectedSourceLanguage']))
+    # [END translate_translate_text]
 
 
 if __name__ == '__main__':