Change NSL graph tutorials to use TF 2.2.x because of a bug in TensorFlow core, and update the README and the INSTALL guides accordingly.

PiperOrigin-RevId: 290796523

Author: arjung

README.md

@@ -49,7 +49,8 @@ from source in various environments, please see the
 [installation guide](g3doc/install.md)
 
 Note that NSL requires a TensorFlow version of 1.15 or higher. NSL also supports
-TensorFlow 2.0.
+TensorFlow 2.x with the exception of v2.1, which contains a bug that is
+incompatible with NSL.
 
 ## Contributing to NSL
 

g3doc/install.md

@@ -12,7 +12,9 @@ Learning (NSL) in TensorFlow:
 *   If you have a unique machine configuration,
     [build NSL](#build-the-neural-structured-learning-pip-package) from source.
 
-Note: NSL requires a TensorFlow version of 1.15 or higher.
+Note: NSL requires a TensorFlow version of 1.15 or higher. NSL also supports
+TensorFlow 2.x with the exception of v2.1, which contains a bug that is
+incompatible with NSL.
 
 ## Install Neural Structured Learning using pip
 

g3doc/tutorials/graph_keras_lstm_imdb.ipynb

@@ -114,7 +114,7 @@
       "source": [
         "## Requirements\n",
         "\n",
-        "1.  Select TensorFlow 2.x to create an interactive development environment with eager execution.\n",
+        "1.  Install TensorFlow 2.2.x to create an interactive development environment with eager execution.\n",
         "2.  Install the Neural Structured Learning package.\n",
         "3.  Install tensorflow-hub."
       ]
@@ -129,11 +129,7 @@
       },
       "outputs": [],
       "source": [
-        "try:\n",
-        "  # %tensorflow_version only exists in Colab.\n",
-        "  %tensorflow_version 2.x\n",
-        "except Exception:\n",
-        "  !pip install tensorflow-gpu>=2.0.0"
+        "!pip install --quiet tf-nightly==2.2.0.dev20200119"
       ]
     },
     {

g3doc/tutorials/graph_keras_mlp_cora.ipynb

@@ -116,7 +116,7 @@
         "id": "hgSLDi0SyBuO"
       },
       "source": [
-        "1.  Select TensorFlow 2.x to create an interactive development environment with eager execution.\n",
+        "1.  Install TensorFlow 2.2.x to create an interactive development environment with eager execution.\n",
         "2.  Install the Neural Structured Learning package."
       ]
     },
@@ -130,11 +130,7 @@
       },
       "outputs": [],
       "source": [
-        "try:\n",
-        "  # %tensorflow_version only exists in Colab.\n",
-        "  %tensorflow_version 2.x\n",
-        "except Exception:\n",
-        "  !pip install tensorflow-gpu>=2.0.0"
+        "!pip install --quiet tf-nightly==2.2.0.dev20200119"
       ]
     },
     {