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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 leaveWhitespace( self ):
 """Extends ``leaveWhitespace`` defined in base class, and also invokes ``leaveWhitespace`` on all contained expressions."""

        self.skipWhitespace = False
        self.exprs = [ e.copy() for e in self.exprs ]
        for e in self.exprs:
            e.leaveWhitespace()
        return self