diff --git a/model/simulationtests/lib/python_plugin_program.csv b/model/simulationtests/lib/python_plugin_program.csv
new file mode 100644
index 000000000..00aecc5b7
--- /dev/null
+++ b/model/simulationtests/lib/python_plugin_program.csv
@@ -0,0 +1,2 @@
+numerator,denominator
+0,0
diff --git a/model/simulationtests/lib/python_plugin_program.py b/model/simulationtests/lib/python_plugin_program.py
new file mode 100644
index 000000000..65e4a9b4c
--- /dev/null
+++ b/model/simulationtests/lib/python_plugin_program.py
@@ -0,0 +1,44 @@
+from pyenergyplus.plugin import EnergyPlusPlugin
+
+import os, sys
+sys.path.append('C:/Python38/Lib/site-packages') # this should (needs to?) be same version as E+'s version
+import pandas as pd
+
+class <%= pluginClassName %>(EnergyPlusPlugin):
+
+    def __init__(self):
+        super().__init__()
+        self.do_setup = True
+
+        self.df = pd.read_csv(os.path.join(os.path.dirname(__file__), 'python_plugin_program.csv'))
+
+    def on_end_of_zone_timestep_before_zone_reporting(self, state) -> int:
+        if self.do_setup:
+            self.data['zone_volumes'] = []
+            self.data['zone_temps'] = []
+            zone_names = <%= model.getThermalZones.map(&:nameString).sort %>
+            for zone_name in zone_names:
+                handle = self.api.exchange.get_internal_variable_handle(state, 'Zone Air Volume', zone_name)
+                zone_volume = self.api.exchange.get_internal_variable_value(state, handle)
+                self.data['zone_volumes'].append(zone_volume)
+                self.data['zone_temps'].append(
+                    self.api.exchange.get_variable_handle(state, 'Zone Mean Air Temperature', zone_name)
+                )
+            self.data['avg_temp_variable'] = self.api.exchange.get_global_handle(state, '<%= py_var.nameString %>')
+            self.data['trend'] = self.api.exchange.get_trend_handle(state, '<%= py_trend_var.nameString %>')
+            self.data['running_avg_temp_variable'] = self.api.exchange.get_global_handle(state, '<%= py_var2.nameString %>')
+            self.do_setup = False
+        zone_temps = list()
+        for t_handle in self.data['zone_temps']:
+            zone_temps.append(self.api.exchange.get_variable_value(state, t_handle))
+        numerator = float(self.df.iloc[0]['numerator'])
+        denominator = float(self.df.iloc[0]['denominator'])
+        for i in range(len(self.data['zone_volumes'])):
+            numerator += self.data['zone_volumes'][i] * zone_temps[i]
+            denominator += self.data['zone_volumes'][i]
+        average_temp = numerator / denominator
+        self.api.exchange.set_global_value(state, self.data['avg_temp_variable'], average_temp)
+
+        past_daily_avg_temp = self.api.exchange.get_trend_average(state, self.data['trend'], 96)
+        self.api.exchange.set_global_value(state, self.data['running_avg_temp_variable'], past_daily_avg_temp)
+        return 0
diff --git a/model/simulationtests/python_plugin_2.rb b/model/simulationtests/python_plugin_2.rb
new file mode 100644
index 000000000..1a21a03d8
--- /dev/null
+++ b/model/simulationtests/python_plugin_2.rb
@@ -0,0 +1,99 @@
+# frozen_string_literal: true
+
+require 'openstudio'
+require_relative 'lib/baseline_model'
+require 'tmpdir'
+require 'erb'
+
+model = BaselineModel.new
+
+# make a 1 story, 100m X 50m, 5 zone core/perimeter building
+model.add_geometry({ 'length' => 100,
+                     'width' => 50,
+                     'num_floors' => 1,
+                     'floor_to_floor_height' => 4,
+                     'plenum_height' => 0,
+                     'perimeter_zone_depth' => 3 })
+
+# assign constructions from a local library to the walls/windows/etc. in the model
+model.set_constructions
+
+# set whole building space type; simplified 90.1-2004 Large Office Whole Building
+model.set_space_type
+
+# add design days to the model (Chicago)
+model.add_design_days
+
+# Add a PythonPlugin:Variable (all OS SDK PythonPluginVariable objects are
+# translated to a single E+ PythonPlugin:Variables (extensible object))
+py_var = OpenStudio::Model::PythonPluginVariable.new(model)
+py_var.setName('AverageBuildingTemp')
+
+# Add a PythonPlugin:OutputVariable for that variable
+py_out_var = OpenStudio::Model::PythonPluginOutputVariable.new(py_var)
+py_out_var.setName('Averaged Building Temperature')
+py_out_var.setTypeofDatainVariable('Averaged')
+py_out_var.setUpdateFrequency('ZoneTimestep')
+py_out_var.setUnits('C')
+
+# Add a regular Output:Variable that references it
+out_var = OpenStudio::Model::OutputVariable.new('PythonPlugin:OutputVariable', model)
+out_var.setKeyValue(py_out_var.nameString)
+out_var.setReportingFrequency('Timestep')
+
+# Add output variables for Zone Mean Air Temperature, so we can compare
+outputVariable = OpenStudio::Model::OutputVariable.new('Zone Mean Air Temperature', model)
+outputVariable.setReportingFrequency('Timestep')
+
+# Trend Variable: while this is a fully functioning object, you're probably
+# best just using a storage variable on the Python side (eg: a list)
+py_trend_var = OpenStudio::Model::PythonPluginTrendVariable.new(py_var)
+py_trend_var.setName('Running Averaged Building Temperature')
+n_timesteps = 24 * model.getTimestep.numberOfTimestepsPerHour
+py_trend_var.setNumberofTimestepstobeLogged(n_timesteps)
+
+py_var2 = OpenStudio::Model::PythonPluginVariable.new(model)
+py_var2.setName('RunningAverageBuildingTemp')
+
+py_out_trend_var = OpenStudio::Model::PythonPluginOutputVariable.new(py_var2)
+py_out_trend_var.setName('Running Averaged Building Temperature')
+py_out_trend_var.setTypeofDatainVariable('Averaged')
+py_out_trend_var.setUpdateFrequency('ZoneTimestep')
+py_out_trend_var.setUnits('C')
+
+out_trend_var = OpenStudio::Model::OutputVariable.new('PythonPlugin:OutputVariable', model)
+out_trend_var.setReportingFrequency('Timestep')
+
+pluginClassName = 'AverageZoneTemps'
+
+# get the python plugin program (erb template)
+pluginTemplatePath = File.join(File.dirname(__FILE__), 'lib/python_plugin_program.py')
+in_py = ''
+File.open(pluginTemplatePath, 'r') do |file|
+  in_py = file.read
+end
+
+dataPath = File.join(File.dirname(__FILE__), 'lib/python_plugin_program.csv')
+OpenStudio::Model::ExternalFile.getExternalFile(model, dataPath)
+
+# configure plugin template with variable values
+renderer = ERB.new(in_py)
+out_py = renderer.result(binding)
+
+# Write it to a temporary directory so we don't pollute the current directory
+# ExternalFile will copy it
+pluginPath = File.join(Dir.tmpdir, 'python_plugin_program.py')
+File.open(pluginPath, 'w') do |file|
+  file << out_py
+end
+
+# create the external file object
+external_file = OpenStudio::Model::ExternalFile.getExternalFile(model, pluginPath)
+external_file = external_file.get
+
+# create the python plugin instance object
+python_plugin_instance = OpenStudio::Model::PythonPluginInstance.new(external_file, pluginClassName)
+python_plugin_instance.setRunDuringWarmupDays(false)
+
+# save the OpenStudio model (.osm)
+model.save_openstudio_osm({ 'osm_save_directory' => Dir.pwd, 'osm_name' => 'in.osm' })
diff --git a/model_tests.rb b/model_tests.rb
index 68cd75f83..f17db2463 100644
--- a/model_tests.rb
+++ b/model_tests.rb
@@ -968,6 +968,15 @@ def test_python_plugin_osm
     result = sim_test('python_plugin.osm')
   end
 
+  def test_python_plugin_2_rb
+    result = sim_test('python_plugin_2.rb')
+  end
+
+  # TODO: To be added in the next official release after: 3.5.0
+  # def test_python_plugin_2_osm
+  # result = sim_test('python_plugin_2.osm')
+  # end
+
   def test_refrigeration_system_rb
     result = sim_test('refrigeration_system.rb')
   end