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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 merge(self, other):
 """Add requirements from 'other' metadata.rb into this one."""

        if not isinstance(other, MetadataRb):
            raise TypeError("MetadataRb to merge should be a 'MetadataRb' "
                            "instance, not %s.", type(other))
        current = self.to_dict()
        new = other.to_dict()

        # compare and gather cookbook dependencies
        meta_writelines = ['%s\n' % self.depends_statement(cbn, meta)
                           for cbn, meta in new.get('depends', {}).items()
                           if cbn not in current.get('depends', {})]

        self.write_statements(meta_writelines)
        return self.to_dict()