How to use the whisper.create function in whisper

def test_file_diff_invalid(self):
        testdb = "test-%s" % self.filename

        self.addCleanup(self._remove, testdb)
        whisper.create(testdb, [(120, 10)])

        whisper.create(self.filename, self.retention)

        # Merging 2 archives with different retentions should fail
        with open(testdb, 'rb') as fh_1:
            with open(self.filename, 'rb+') as fh_2:
                with AssertRaisesException(
                        NotImplementedError(
                            'test-db.wsp and db.wsp archive configurations are '
                            'unalike. Resize the input before diffing')):
                    whisper.file_diff(fh_1, fh_2)

def test_create_and_info(self):
        """
        Create a db and use info() to validate
        """
        # check if invalid configuration fails successfully
        for retention in (0, []):
            with AssertRaisesException(
                    whisper.InvalidConfiguration(
                        'You must specify at least one archive configuration!')):
                whisper.create(self.filename, retention)

        # create a new db with a valid configuration
        whisper.create(self.filename, self.retention)

        # Ensure another file can't be created when one exists already
        with AssertRaisesException(
                whisper.InvalidConfiguration(
                    'File {0} already exists!'.format(self.filename))):
            whisper.create(self.filename, self.retention)

        info = whisper.info(self.filename)

        # check header information
        self.assertEqual(info['maxRetention'],
                         max([a[0] * a[1] for a in self.retention]))
        self.assertEqual(info['aggregationMethod'], 'average')
        self.assertEqual(info['xFilesFactor'], 0.5)

        # check archive information

def test_file_fetch_edge_cases(self):
        """
        Test some of the edge cases in file_fetch() that should return
        None or raise an exception
        """
        whisper.create(self.filename, [(1, 60)])

        with open(self.filename, 'rb') as fh:
            msg = "Invalid time interval: from time '{0}' is after until time '{1}'"
            until_time = 0
            from_time = int(time.time()) + 100

            with AssertRaisesException(
                    whisper.InvalidTimeInterval(msg.format(from_time, until_time))):
                whisper.file_fetch(fh, fromTime=from_time, untilTime=until_time)

            # fromTime > now aka metrics from the future
            self.assertIsNone(
                whisper.file_fetch(fh, fromTime=int(time.time()) + 100,
                                   untilTime=int(time.time()) + 200),
            )

def test_normal(self):
        whisper.create(self.filename, [(1, 60), (60, 60)])

        whisper.CACHE_HEADERS = True
        whisper.info(self.filename)
        whisper.info(self.filename)
        whisper.CACHE_HEADERS = False

def test_diff(self):
        testdb = "test-%s" % self.filename

        now = int(time.time())

        self.addCleanup(self._remove, testdb)
        whisper.create(testdb, self.retention)

        whisper.create(self.filename, self.retention)

        whisper.update(testdb, 1.0, now)
        whisper.update(self.filename, 2.0, now)

        results = whisper.diff(testdb, self.filename)

        expected = [(0, [(int(now), 1.0, 2.0)], 1), (1, [], 0)]

        self.assertEqual(results, expected)

def test_diff_with_empty(self):
        testdb = "test-%s" % self.filename

        now = time.time()

        self.addCleanup(self._remove, testdb)
        whisper.create(testdb, self.retention)

        whisper.create(self.filename, self.retention)

        whisper.update(testdb, 1.0, now)
        whisper.update(self.filename, 2.0, now)

        # Purposefully insert nulls to strip out
        previous = now - self.retention[0][0]
        whisper.update(testdb, float('NaN'), previous)

        results = whisper.diff(testdb, self.filename, ignore_empty=True)
        self.assertEqual(
            results,
            [(0, [(int(now), 1.0, 2.0)], 1), (1, [], 0)],
        )

        results_empties = whisper.diff(testdb, self.filename, ignore_empty=False)
        expected = [(0, [(int(previous), float('NaN'), None), (int(now), 1.0, 2.0)], 2), (1, [], 0)]

sys.exit(0)

if len(args) < 2:
  option_parser.print_help()
  sys.exit(1)

path = args[0]
archives = [whisper.parseRetentionDef(retentionDef)
            for retentionDef in args[1:]]

if os.path.exists(path) and options.overwrite:
  print('Overwriting existing file: %s' % path)
  os.unlink(path)

try:
  whisper.create(path, archives, xFilesFactor=options.xFilesFactor,
                 aggregationMethod=options.aggregationMethod, sparse=options.sparse,
                 useFallocate=options.fallocate)
except whisper.WhisperException as exc:
  raise SystemExit('[ERROR] %s' % str(exc))

size = os.stat(path).st_size
print('Created: %s (%d bytes)' % (path, size))

def _create(self):
        """Create the Whisper file on disk"""
        if not os.path.exists(settings.SALMON_WHISPER_DB_PATH):
            os.makedirs(settings.SALMON_WHISPER_DB_PATH)
        archives = [whisper.parseRetentionDef(retentionDef)
                    for retentionDef in settings.ARCHIVES.split(",")]
        whisper.create(self.path, archives,
                       xFilesFactor=settings.XFILEFACTOR,
                       aggregationMethod=settings.AGGREGATION_METHOD)

def handle(self):
        points = 0
        for metric in self.redis.smembers(METRICS):
            values = self.redis.zrange(metric, 0, -1)
            points += len(values)
            f = target_to_path(self.path, metric)
            d = os.path.dirname(f)
            if d not in self.dirs:
                if not os.path.isdir(d):
                    os.makedirs(d)
                self.dirs.add(d)
            if not os.path.exists(f):
                whisper.create(f, [(10, 1000)])  # [FIXME] hardcoded values
            whisper.update_many(f, [struct.unpack('!ff', a) for a in values])
            if len(values):
                self.redis.zrem(metric, *values)
        self.metric(METRIC_POINTS, points)

def create(self, metric, retentions, xfilesfactor, aggregation_method):
      path = self.getFilesystemPath(metric)
      directory = dirname(path)
      try:
        if not exists(directory):
          os.makedirs(directory)
      except OSError as e:
        log.err("%s" % e)

      whisper.create(path, retentions, xfilesfactor, aggregation_method,
                     self.sparse_create, self.fallocate_create)