extend this work to Python 2.7 and let user choose between either Python 2 or Python 3

Author: sjentzsch

ansible/roles/aws_polly/tasks/main.yml

@@ -4,7 +4,7 @@
   pip:
     name: "{{ item }}"
     state: latest
-    executable: pip3
+    executable: "{{ pip_version }}"
     extra_args: --user
   with_items:
     - boto3

ansible/roles/local_load_config/tasks/main.yml

@@ -10,3 +10,14 @@
 - name: Overwrite Configuration file from user-specific local configuration file
   include_vars: ../config/config.local.yml
   when: config_st.stat.exists == True
+
+- name: Assert Python version properly set
+  assert:
+    that:
+      - "python_version == 2 or python_version == 3"
+    msg: "python_version must be set to either 2 or 3 in config/config.local.yml"
+
+- name: Set variables according to Python version set to {{ python_version }}
+  set_fact:
+    pip_version: "{{ 'pip2' if python_version == 2 else 'pip3' }}"
+    python_name: "{{ 'python' if python_version == 2 else 'python3' }}"

ansible/roles/opencv/tasks/main.yml

@@ -124,7 +124,7 @@
         -D WITH_OPENGL=ON
         -D OPENCV_EXTRA_MODULES_PATH=../../opencv_contrib/modules
         -D WITH_IPP=ON
-        -D PYTHON_DEFAULT_EXECUTABLE=$(which python3)
+        -D PYTHON_DEFAULT_EXECUTABLE=$(which {{ python_name }})
         -D INSTALL_PYTHON_EXAMPLES=ON
         -D BUILD_PERF_TESTS=OFF
         -D BUILD_TESTS=OFF

ansible/roles/tensorflow/tasks/main.yml

@@ -5,7 +5,7 @@
   become: yes
 
 - name: Install common packages (mostly python and pip)
-  apt: name={{item}} state=latest
+  apt: name={{ item }} state=latest
   with_items:
     - aptitude
     - colordiff
@@ -14,9 +14,9 @@
     - python3-dev
     - python-pip
     - python3-pip
-    - python3-numpy
-    - python3-wheel
-    - python3-tk
+    - "{{ python_name }}-numpy"
+    - "{{ python_name }}-wheel"
+    - "{{ python_name }}-tk"
     - unzip
     - debconf
     - debconf-utils
@@ -36,19 +36,19 @@
 - include_tasks: tf_gpu_req.yml
   when: tf_enable_gpu
 
-- name: Install latest tensorflow with native pip3 (no GPU support)
+- name: Install latest tensorflow with native {{ pip_version }} package (no GPU support)
   pip:
     name: tensorflow
     state: latest
-    executable: pip3
+    executable: "{{ pip_version }}"
   become: yes
   when: not tf_build_from_source and not tf_enable_gpu
 
-- name: Install latest tensorflow with native pip3 (with GPU support)
+- name: Install latest tensorflow with native {{ pip_version }} package (with GPU support)
   pip:
     name: tensorflow-gpu
     state: latest
-    executable: pip3
+    executable: "{{ pip_version }}"
   become: yes
   when: not tf_build_from_source and tf_enable_gpu
 

ansible/roles/tf_object_detection/tasks/main.yml

@@ -10,11 +10,11 @@
     - protobuf-compiler
   become: yes
 
-- name: Install dependencies through pip
+- name: Install dependencies through {{ pip_version }}
   pip:
     name: "{{ item }}"
     state: latest
-    executable: pip3
+    executable: "{{ pip_version }}"
   with_items:
     - pillow
     - lxml
@@ -32,7 +32,7 @@
 - name: Install xlib required for screen capturing
   apt: name={{ item }} state=latest
   with_items:
-    - python3-xlib
+    - "{{ python_name }}-xlib"
     - libx11-dev
   become: yes
 

config/config.local.sample.yml

@@ -3,7 +3,7 @@
 ## ATTENTION: Do not modify 'config.local.sample.yml' !! You should create a copy named 'config.local.yml' and modify that one !!
 
 
-## Tensorflow
+## TensorFlow
 
 tf_enable_gpu: false
 
@@ -15,6 +15,7 @@ tf_models_repo_name: tensorflow_models
 tf_models_repo_url: tensorflow/models
 tf_models_repo_branch: master
 
+
 ## OpenCV
 
 opencv_version: 3.3.1
@@ -23,3 +24,10 @@ opencv_contrib_repo_branch: 3.3.1
 opencv_extra_repo_branch: 3.3.1
 opencv_build_examples: OFF
 opencv_force_rebuild: false
+
+
+## Python
+
+# put either 2 for Python 2.7 or 3 for Python 3.5
+# Note: When switching between versions, force rebuild of OpenCV and TensorFlow once (i.e., set opencv_force_rebuild to true)
+python_version: 3

stuff/__init__.py

@@ -8,9 +8,11 @@
 from contextlib import closing
 import os
 import sys
-from contextlib import suppress
 from threading import Thread
-from queue import LifoQueue, Empty
+if sys.version_info.major < 3:
+    from Queue import LifoQueue, Empty
+else:
+    from queue import LifoQueue, Empty
 from time import sleep
 from tempfile import gettempdir
 
@@ -30,8 +32,11 @@ def __init__(self):
 
     def request(self, text):
         """Clear queue (ignore it being empty) and add text, both non-blocking"""
-        with suppress(Empty):
+        # for Python 3.4+ this could be written as: with suppress(Empty): ... assuming: from contextlib import suppress
+        try:
             self._speak_queue.get_nowait()
+        except Empty:
+            pass
         self._speak_queue.put_nowait(text)
 
     def run(self):