'squashmigrations accepts a starting migration.'

def test_squashmigrations_valid_start(self):

    out = io.StringIO()
    with self.temporary_migration_module(module='migrations.test_migrations_no_changes') as migration_dir:
        call_command('squashmigrations', 'migrations', '0002', '0003', interactive=False, verbosity=1, stdout=out)
        squashed_migration_file = os.path.join(migration_dir, '0002_second_squashed_0003_third.py')
        with open(squashed_migration_file, 'r', encoding='utf-8') as fp:
            content = fp.read()
            self.assertIn("                                ('migrations',    '0001_initial')", content)
            self.assertNotIn('initial    =    True', content)
    out = out.getvalue()
    self.assertNotIn('    -    0001_initial', out)
    self.assertIn('    -    0002_second', out)
    self.assertIn('    -    0003_third', out)
