diff --git a/python/helpers/generator3.py b/python/helpers/generator3.py
index 737b29f15a6c..d09f6d918e18 100644
--- a/python/helpers/generator3.py
+++ b/python/helpers/generator3.py
@@ -1,12 +1,6 @@
 # encoding: utf-8
 import atexit
 import zipfile
-import sys
-
-
-if hasattr(sys, 'dont_write_bytecode'):
-    sys.dont_write_bytecode = True
-
 
 # TODO: Move all CLR-specific functions to clr_tools
 
diff --git a/python/src/com/jetbrains/python/documentation/PyStructuredDocstringFormatter.java b/python/src/com/jetbrains/python/documentation/PyStructuredDocstringFormatter.java
index e533f98609e9..f74be9bdaf9d 100644
--- a/python/src/com/jetbrains/python/documentation/PyStructuredDocstringFormatter.java
+++ b/python/src/com/jetbrains/python/documentation/PyStructuredDocstringFormatter.java
@@ -28,6 +28,7 @@ import com.intellij.psi.PsiElement;
 import com.jetbrains.python.PythonHelpersLocator;
 import com.jetbrains.python.psi.StructuredDocString;
 import com.jetbrains.python.sdk.PySdkUtil;
+import com.jetbrains.python.sdk.PythonEnvUtil;
 import com.jetbrains.python.sdk.PythonSdkType;
 import com.jetbrains.python.toolbox.Substring;
 import org.jetbrains.annotations.NotNull;
@@ -37,7 +38,9 @@ import java.io.File;
 import java.nio.ByteBuffer;
 import java.nio.charset.Charset;
 import java.util.ArrayList;
+import java.util.HashMap;
 import java.util.List;
+import java.util.Map;
 
 /**
  * @author yole
@@ -105,9 +108,11 @@ public class PyStructuredDocstringFormatter {
     final byte[] data = new byte[encoded.limit()];
     encoded.get(data);
 
+    final Map<String, String> env = new HashMap<String, String>();
+    PythonEnvUtil.setPythonDontWriteBytecode(env);
 
     final ProcessOutput output = PySdkUtil.getProcessOutput(new File(sdkHome).getParent(), new String[]{sdkHome, formatter},
-                                                            null, 5000, data, true);
+                                                            env, 5000, data, true);
     if (output.isTimeout()) {
       LOG.info("timeout when calculating docstring");
       return null;
diff --git a/python/src/com/jetbrains/python/packaging/PyPackageManagerImpl.java b/python/src/com/jetbrains/python/packaging/PyPackageManagerImpl.java
index e85a5a80a45a..d949fe54a036 100644
--- a/python/src/com/jetbrains/python/packaging/PyPackageManagerImpl.java
+++ b/python/src/com/jetbrains/python/packaging/PyPackageManagerImpl.java
@@ -15,7 +15,6 @@
  */
 package com.jetbrains.python.packaging;
 
-import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.Lists;
 import com.intellij.execution.ExecutionException;
 import com.intellij.execution.RunCanceledByUserException;
@@ -49,6 +48,7 @@ import com.jetbrains.python.psi.PyExpression;
 import com.jetbrains.python.psi.PyListLiteralExpression;
 import com.jetbrains.python.psi.PyStringLiteralExpression;
 import com.jetbrains.python.sdk.PySdkUtil;
+import com.jetbrains.python.sdk.PythonEnvUtil;
 import com.jetbrains.python.sdk.PythonSdkType;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
@@ -469,7 +469,9 @@ public class PyPackageManagerImpl extends PyPackageManager {
 
     try {
       final Process process;
-      final Map<String, String> environment = PySdkUtil.mergeEnvVariables(System.getenv(), ImmutableMap.of("PYTHONUNBUFFERED", "1"));
+      final Map<String, String> environment = new HashMap<String, String>(System.getenv());
+      PythonEnvUtil.setPythonUnbuffered(environment);
+      PythonEnvUtil.setPythonDontWriteBytecode(environment);
       final GeneralCommandLine commandLine = new GeneralCommandLine(cmdline).withWorkDirectory(workingDir).withEnvironment(environment);
       if (useSudo) {
         process = ExecUtil.sudo(commandLine, "Please enter your password to make changes in system packages: ");
diff --git a/python/src/com/jetbrains/python/sdk/PythonEnvUtil.java b/python/src/com/jetbrains/python/sdk/PythonEnvUtil.java
index 50c4881c3a2d..7b4184fd00a0 100644
--- a/python/src/com/jetbrains/python/sdk/PythonEnvUtil.java
+++ b/python/src/com/jetbrains/python/sdk/PythonEnvUtil.java
@@ -15,7 +15,6 @@
  */
 package com.jetbrains.python.sdk;
 
-import com.google.common.collect.Lists;
 import com.google.common.collect.Sets;
 import com.intellij.openapi.util.text.StringUtil;
 import org.jetbrains.annotations.NotNull;
@@ -23,7 +22,6 @@ import org.jetbrains.annotations.Nullable;
 
 import java.io.File;
 import java.util.Collection;
-import java.util.List;
 import java.util.Map;
 import java.util.Set;
 
@@ -35,6 +33,7 @@ public class PythonEnvUtil {
   @SuppressWarnings("SpellCheckingInspection") public static final String PYTHONUNBUFFERED = "PYTHONUNBUFFERED";
   @SuppressWarnings("SpellCheckingInspection") public static final String PYTHONIOENCODING = "PYTHONIOENCODING";
   @SuppressWarnings("SpellCheckingInspection") public static final String IPYTHONENABLE = "IPYTHONENABLE";
+  @SuppressWarnings("SpellCheckingInspection") public static final String PYTHONDONTWRITEBYTECODE = "PYTHONDONTWRITEBYTECODE";
 
   private PythonEnvUtil() { }
 
@@ -86,4 +85,10 @@ public class PythonEnvUtil {
   public static void addToPythonPath(@NotNull Map<String, String> env, String value) {
     addPathToEnv(env, PYTHONPATH, value);
   }
+
+  @NotNull
+  public static Map<String, String> setPythonDontWriteBytecode(@NotNull Map<String, String> env) {
+    env.put(PYTHONDONTWRITEBYTECODE, "1");
+    return env;
+  }
 }
diff --git a/python/src/com/jetbrains/python/sdk/skeletons/PySkeletonGenerator.java b/python/src/com/jetbrains/python/sdk/skeletons/PySkeletonGenerator.java
index 90d1921f920c..672137d4a150 100644
--- a/python/src/com/jetbrains/python/sdk/skeletons/PySkeletonGenerator.java
+++ b/python/src/com/jetbrains/python/sdk/skeletons/PySkeletonGenerator.java
@@ -29,6 +29,7 @@ import com.intellij.util.Consumer;
 import com.jetbrains.python.PythonHelpersLocator;
 import com.jetbrains.python.sdk.InvalidSdkException;
 import com.jetbrains.python.sdk.PySdkUtil;
+import com.jetbrains.python.sdk.PythonEnvUtil;
 import com.jetbrains.python.sdk.PythonSdkType;
 import com.jetbrains.python.sdk.flavors.IronPythonSdkFlavor;
 import com.jetbrains.python.sdk.flavors.PythonSdkFlavor;
@@ -171,12 +172,9 @@ public class PySkeletonGenerator {
 
   protected ProcessOutput getProcessOutput(String homePath, String[] commandLine, Map<String, String> extraEnv,
                                            int timeout) throws InvalidSdkException {
-    return PySdkUtil.getProcessOutput(
-      homePath,
-      commandLine,
-      extraEnv,
-      timeout
-    );
+    final Map<String, String> env = extraEnv != null ? new HashMap<String, String>(extraEnv) : new HashMap<String, String>();
+    PythonEnvUtil.setPythonDontWriteBytecode(env);
+    return PySdkUtil.getProcessOutput(homePath, commandLine, env, timeout);
   }
 
   public void generateBuiltinSkeletons(@NotNull Sdk sdk) throws InvalidSdkException {