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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_user( self, name, **attrs ):
 """Add a user to config."""

        if self.user_exists(name):
            raise KubeConfError("user with the given name already exists.")

        users = self.get_users()
        
        # Add parameters.
        new_user = {'name': name, 'user':{}}
        attrs_ = new_user['user']
        attrs_.update(attrs)
        users.append(new_user)