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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def load( self, stats ):
 """Build a squaremap-compatible model from a pstats class"""

        rows = self.rows
        for func, raw in stats.iteritems():
            try:
                rows[func] = row = PStatRow( func,raw )
            except ValueError, err:
                log.info( 'Null row: %s', func )
        for row in rows.itervalues():
            row.weave( rows )
        return self.find_root( rows )