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# regarding copyright ownership. The ASF licenses this file
# to you under the Apache License, Version 2.0 (the
# "License"); you may not use this file except in compliance
# with the License. You may obtain a copy of the License at
#
#   http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing,
# software distributed under the License is distributed on an
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# under the License.

import unittest

from . import flatten


class FlattenTest(unittest.TestCase):
  def test_flatten(self):
    expected = ['A', 'B', 'C', 'D']
    actual = list(flatten([['A'], ['B', 'C'], ['D']]))
    self.assertEqual(expected, actual)
