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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 add_replace(self, selector, replacement, upsert=False, collation=None):
 """Create a replace document and add it to the list of ops. """

        validate_ok_for_replace(replacement)
        cmd = SON([('q', selector), ('u', replacement),
                   ('multi', False), ('upsert', upsert)])
        collation = validate_collation_or_none(collation)
        if collation is not None:
            self.uses_collation = True
            cmd['collation'] = collation
        self.ops.append((_UPDATE, cmd))