diff --git a/bin/python_venv b/bin/python_venv
index 5c1b381..3a68764 100755
--- a/bin/python_venv
+++ b/bin/python_venv
@@ -7,8 +7,21 @@
 #
 # This script will set up a virtualenv when it has not been created yet and
 # executes the Python interpreter.
+#
+# The canonical version of this script is in infra_virtualenv repository.
+# See infra_virtualenv/README.md about how to adopt virtualenv to your project.
+
 set -eu
 
+# Change this constant to the path(s) to infra_virtualenv directory when you
+# copy this script to other repos.
+# A path can be a relative path from this script, or an absolute path. If this
+# array contains multiple paths, they are searched in the listed order.
+readonly -a infra_virtualenv_paths=(
+    "../../../../../infra_virtualenv"
+    "/opt/infra_virtualenv"
+)
+
 readonly bin_dir="$(readlink -e -- "$(dirname -- "$0")")"
 if [[ ! -d "${bin_dir}" ]]; then
     echo "ERROR: Can not locate the location of python_env!" >&2
@@ -17,41 +30,45 @@
 
 realpath() {
     pushd "${bin_dir}" > /dev/null 2>&1
-    readlink -f -- "$1"
+    readlink -e -- "$1"
     popd > /dev/null 2>&1
 }
 
-err_infra_virtualenv() {
-    echo "ERROR: infra_virtualenv directory cannot be located." >&2
-    echo "You need to update a constant inside python_venv, or your " >&2
-    echo "checkout might be incomplete." >&2
-    exit 1
+find_create_venv() {
+    local p
+    for p in "${infra_virtualenv_paths[@]}"; do
+        local create_venv=$(realpath "${p}/bin/create_venv")
+        if [[ -f "${create_venv}" ]]; then
+            echo "${create_venv}"
+            break
+        fi
+    done
 }
 
-if [[ -d $(realpath ../../../../../infra_virtualenv) ]]; then
-    readonly infra_virtualenv_path=$(realpath ../../../../../infra_virtualenv)
-elif [[ -d /opt/infra_virtualenv ]]; then
-    readonly infra_virtualenv_path=/opt/infra_virtualenv
-else
-    err_infra_virtualenv
-fi
-
-readonly create_venv="${infra_virtualenv_path}/bin/create_venv"
+readonly create_venv=$(find_create_venv)
 if [[ ! -f "${create_venv}" ]]; then
-    err_infra_virtualenv
+    cat <<EOF >&2
+ERROR: create_venv script could not be located.
+You need to update a constant inside python_venv, or your checkout might be
+incomplete.
+EOF
+    exit 1
 fi
 
 readonly extra_imports_dir=$(realpath ../venv)
 if [[ ! -d "${extra_imports_dir}" ]]; then
-    echo "ERROR: venv directory is not found at ${bin_dir}/.." >&2
-    echo "See infra_virtualenv/README.md for details." >&2
+    cat <<EOF >&2
+ERROR: ${bin_dir}/../venv does not exist
+See infra_virtualenv/README.md for details.
+EOF
     exit 1
 fi
 
 readonly venv_dir=$("${create_venv}" "${extra_imports_dir}/requirements.txt")
 if [[ ! -d "${venv_dir}" ]]; then
-    echo "ERROR: Failed to set up virtualenv" >&2
+    echo "ERROR: Failed to set up a virtualenv." >&2
     exit 1
 fi
+
 export PYTHONPATH="${extra_imports_dir}"
 exec "${venv_dir}/bin/python" "$@"