content: # Copyright (c) Meta Platforms, Inc. and affiliates.
  #
  # This source code is licensed under the MIT license found in the
  # LICENSE file in the root directory of this source tree.
  import math
  from typing import Optional, Union
  
  import torch
  
  TEST_EPS = 5e-7
  EPS = 1e-10
  PI = math.pi
  
  __FROM_THESEUS_LAYER_TOKEN__ = "__FROM_THESEUS_LAYER_TOKEN__"
  
  
  _NON_ZERO = 1.0
  
  _INF = torch.inf
  
  _NEAR_ZERO_D_ONE_MINUS_COSINE_BY_THETA2 = -1 / 12.0
  
  _NEAR_ZERO_D_THETA_MINUS_SINE_BY_THETA3 = -1 / 60.0
  
  DeviceType = Optional[Union[str, torch.device]]
  