diff --git a/CMakeLists.txt b/home1/anruliu/workspace/company/file/CMakeLists.txt
index f0e62d3..ea2d5ff 100644
--- a/CMakeLists.txt
+++ b/home1/anruliu/workspace/company/file/CMakeLists.txt
@@ -302,24 +302,24 @@ ENDIF()
 
 OPTION(BUILD_BULLET3 "Set when you want to build Bullet 3" ON)
 # Optional Python configuration
-# builds pybullet automatically if all the requirements are met
-SET(PYTHON_VERSION_PYBULLET "" CACHE STRING "Python version pybullet will use.")
-SET(Python_ADDITIONAL_VERSIONS 3 3.6 3.5 3.4 3.3 3.2 3.1 3.0 2.7 2.7.12 2.7.10 2.7.3 )
-SET_PROPERTY(CACHE PYTHON_VERSION_PYBULLET PROPERTY STRINGS ${Python_ADDITIONAL_VERSIONS})
-SET(CMAKE_MODULE_PATH ${CMAKE_CURRENT_SOURCE_DIR}/build3/cmake ${CMAKE_MODULE_PATH})
-OPTION(EXACT_PYTHON_VERSION "Require Python and match PYTHON_VERSION_PYBULLET exactly, e.g. 2.7.12" OFF)
-IF(EXACT_PYTHON_VERSION)
-  set(EXACT_PYTHON_VERSION_FLAG EXACT REQUIRED)
-ENDIF(EXACT_PYTHON_VERSION)
-# first find the python interpreter
-FIND_PACKAGE(PythonInterp ${PYTHON_VERSION_PYBULLET} ${EXACT_PYTHON_VERSION_FLAG})
-# python library should exactly match that of the interpreter
-FIND_PACKAGE(PythonLibs ${PYTHON_VERSION_STRING} EXACT)
-SET(DEFAULT_BUILD_PYBULLET OFF)
-IF(PYTHONLIBS_FOUND)
-	SET(DEFAULT_BUILD_PYBULLET ON)
-ENDIF(PYTHONLIBS_FOUND)
-OPTION(BUILD_PYBULLET "Set when you want to build pybullet (Python bindings for Bullet)" ${DEFAULT_BUILD_PYBULLET})
+# Will not probe environment for Python configuration (which can abort the
+# build process) unless you explicitly turn on BUILD_PYBULLET.
+OPTION(BUILD_PYBULLET "Set when you want to build pybullet (Python bindings for Bullet)" OFF)
+IF(BUILD_PYBULLET)
+	SET(PYTHON_VERSION_PYBULLET "" CACHE STRING "Python version pybullet will use.")
+	SET(Python_ADDITIONAL_VERSIONS 3 3.6 3.5 3.4 3.3 3.2 3.1 3.0 2.7 2.7.12 2.7.10 2.7.3 )
+	SET_PROPERTY(CACHE PYTHON_VERSION_PYBULLET PROPERTY STRINGS ${Python_ADDITIONAL_VERSIONS})
+	SET(CMAKE_MODULE_PATH ${CMAKE_CURRENT_SOURCE_DIR}/build3/cmake ${CMAKE_MODULE_PATH})
+	OPTION(EXACT_PYTHON_VERSION "Require Python and match PYTHON_VERSION_PYBULLET exactly, e.g. 2.7.12" OFF)
+	IF(EXACT_PYTHON_VERSION)
+		set(EXACT_PYTHON_VERSION_FLAG EXACT REQUIRED)
+	ENDIF(EXACT_PYTHON_VERSION)
+	# first find the python interpreter
+	FIND_PACKAGE(PythonInterp ${PYTHON_VERSION_PYBULLET} ${EXACT_PYTHON_VERSION_FLAG})
+	# python library should exactly match that of the interpreter
+	# the following can result in fatal error if you don't have the right python configuration
+	FIND_PACKAGE(PythonLibs ${PYTHON_VERSION_STRING} EXACT)
+ENDIF(BUILD_PYBULLET)
 
 OPTION(BUILD_ENET "Set when you want to build apps with enet UDP networking support" ON)
 OPTION(BUILD_CLSOCKET "Set when you want to build apps with enet TCP networking support" ON)