How to read the SQL Server query plan file using TSQL

Here I am trying to read sql server plan (Execution query Plan) file from ssms query.

DECLARE @plancontents xml,@xml XML
SET @plancontents=(SELECT * FROM OPENROWSET(BULK 'P:\Users\hpatterson\Documents\myplan.sqlplan', SINGLE_CLOB) x)
--Get rid of the namespace stuff
--SET @plancontents=REPLACE(@plancontents,'xmlns="http://schemas.microsoft.com/sqlserver/2004/07/showplan"','')
--Now put that into our XML variable
SET @xml=cast(@plancontents as xml)

--DECLARE @xml XML
--select @xml=query_plan from sys.dm_exec_query_plan 
select @xml
---- notice the removed
---- xmlns=http://schemas.microsoft.com/sqlserver/2004/07/showplan 
---- attribute

-- go through all the execution plan nodes, get the attributes and sort on them
;with xmlnamespaces (default 'http://schemas.microsoft.com/sqlserver/2004/07/showplan')
	SELECT c.value('.[1]/@PhysicalOp', 'nvarchar(max)') as PhysicalOp,
	c.value('.[1]/@LogicalOp', 'nvarchar(max)') as LogicalOp,
	c.value('.[1]/@AvgRowSize', 'nvarchar(max)') as AvgRowSize,
	c.value('.[1]/@TableCardinality', 'nvarchar(max)') as TableCardinality,
	c.value('.[1]/@Parallel', 'nvarchar(max)') as Parallel,
	c.value('.[1]/@EstimateRebinds', 'nvarchar(max)') as EstimateRebinds,
	c.value('.[1]/@EstimateRewinds', 'nvarchar(max)') as EstimateRewinds,
	c.value('.[1]/@NodeId', 'nvarchar(max)') as NodeId,
	c.value('.[1]/@EstimatedTotalSubtreeCost', 'nvarchar(max)') as EstimatedTotalSubtreeCost,
    c.value('.[1]/@EstimateRows', 'nvarchar(max)') as EstimateRows,
    c.value('.[1]/@EstimateIO', 'nvarchar(max)') as EstimateIO,
    c.value('.[1]/@EstimateCPU', 'nvarchar(max)') as EstimateCPU,
    -- this returns just the node xml for easier inspection
    c.query('.') as ExecPlanNode        
FROM   -- this returns only nodes with the name RelOp even if they are children of children
       @xml.nodes('//child::RelOp') T(c)
ORDER BY EstimatedTotalSubtreeCost DESC