Revert "remove max_tokens from example (google#425)" (google#435)

This reverts commit e285bb4.

Author: MarkDaoust

site/en/gemini-api/docs/get-started/python.ipynb

@@ -1752,6 +1752,7 @@
         "        # Only one candidate for now.\n",
         "        candidate_count=1,\n",
         "        stop_sequences=['x'],\n",
+        "        max_output_tokens=20,\n",
         "        temperature=1.0)\n",
         ")"
       ]
@@ -1779,6 +1780,10 @@
       ],
       "source": [
         "text = response.text\n",
+        "\n",
+        "if response.candidates[0].finish_reason.name == \"MAX_TOKENS\":\n",
+        "    text += '...'\n",
+        "\n",
         "to_markdown(text)"
       ]
     },