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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_error(self, path, error):
 """Add error message for given field path. Example: :: builder = ValidationErrorBuilder() builder.add_error('foo.bar.baz', 'Some error') print builder.errors # => {'foo': {'bar': {'baz': 'Some error'}}} :param str path: '.'-separated list of field names :param str error: Error message """

        self.errors = merge_errors(self.errors, self._make_error(path, error))