old_contents: {
  	"name" : "Purchase Management",
  	"version" : "1.0",
  	"author" : "Tiny",
  	"website" : "http://tinyerp.com/module_purchase.html",
  	"depends" : ["base", "account", "stock"],
  	"category" : "Generic Modules/Sales & Purchases",
  	"init_xml" : [],
  	"demo_xml" : ["purchase_demo.xml", "purchase_unit_test.xml"],
  	"update_xml" : [
  		"purchase_workflow.xml", 
  		"purchase_sequence.xml", 
  		"purchase_data.xml", 
  		"purchase_view.xml", 
  		"purchase_report.xml", 
  		"purchase_wizard.xml",
  		"stock_view.xml"
  	],
  	"active": False,
  	"installable": True
  }
  
new_contents: {
  	"name" : "Purchase Management",
  	"version" : "1.0",
  	"author" : "Tiny",
  	"website" : "http://tinyerp.com/module_purchase.html",
  	"depends" : ["base", "account", "stock"],
  	"category" : "Generic Modules/Sales & Purchases",
  	"init_xml" : [],
  	"demo_xml" : ["purchase_demo.xml", "purchase_unit_test.xml"],
  	"update_xml" : [
  		"purchase_workflow.xml", 
  		"purchase_sequence.xml", 
  		"purchase_data.xml", 
  		"purchase_view.xml", 
  		"purchase_report.xml", 
  		"purchase_wizard.xml",
  		"stock_view.xml",
  		"purchase_security.xml"
  	],
  	"active": False,
  	"installable": True
  }
  
subject: Add purchase_security.xml file entry in update_xml section