how to add a query layer to a mxd in a python script

I want to add a query layer to an arcmap document so that whenever i have a db data update, it is reflected in my ma and I can update my service through python script. This is my script so far...

import arcpy
from arcpy import env
arcpy.env.overWriteOutput = 1

# define local variables
wrkspc = 'C:/ArcGIS_Workspace/'
mxd = arcpy.mapping.MapDocument(wrkspc + 'scripts/Trial.mxd')

input_db_name = "Database Connections/xxx.sde"
outLayer = "DynamicQueryLayer"
out_layer_name = wrkspc +"/shapefiles/DynamicQueryLayer.lyr"
query = "SELECT * FROM TEST_TABLE"

#unique key for the table
oid_field = "schema.TEST_TABLE.TEST_ID"

try:

    # Create a query layer
    arcpy.MakeQueryLayer_management (input_db_name, outLayer, query, oid_field)

    # save the created query layer
    arcpy.SaveToLayerFile_management(outLayer, out_layer_name, "ABSOLUTE")

    # Get the created layer
    lyr = arcpy.mapping.Layer(out_layer_name)

    # get the data frame of the given mxd
    data_frame = arcpy.mapping.ListDataFrames(mxd)[0]

    # Switch to data view
    mxd.activeView = data_frame.name

    arcpy.mapping.AddLayer(data_frame, lyr, 'TOP')
    print "Added layer to the MXD ..."

    mxd.save()
    print "MXD saved..."    
except Exception, e:
    # If an error occurred, print line number and error message
    import traceback, sys
    tb = sys.exc_info()[2]
    print "Line %i" % tb.tb_lineno
    print e.message

I get this error. ERROR 000732: Input Features: Dataset DynamicQueryLayer does not exist or is not supported.

I am sure there is a way to save the created query layer as a layer file.Any help is greatly appreciated.