old_contents: # import all class inside framework into fluid module
  import framework
  from framework import *
  # import all class inside executor into fluid module
  import executor
  from executor import *
  
  import io
  import evaluator
  import initializer
  import layers
  import nets
  import optimizer
  import backward
  import regularizer
  from param_attr import ParamAttr
  
  from core import LoDTensor, CPUPlace, GPUPlace
  
  Tensor = LoDTensor
  __all__ = framework.__all__ + executor.__all__ + [
      'io', 'initializer', 'layers', 'nets', 'optimizer', 'backward',
      'regularizer', 'LoDTensor', 'CPUPlace', 'GPUPlace', 'Tensor', 'ParamAttr'
  ]
  
  
  def __read_gflags_from_env__():
      """
      Enable reading gflags from environment variables.
      
      Returns:
          None
      """
      import sys
      import core
      read_env_flags = ['use_pinned_memory']
      if core.is_compile_gpu():
          read_env_flags.append('fraction_of_gpu_memory_to_use')
      core.init_gflags(sys.argv + ["--tryfromenv=" + ",".join(read_env_flags)])
  
  
  __read_gflags_from_env__()
  
new_contents: # import all class inside framework into fluid module
  import framework
  from framework import *
  # import all class inside executor into fluid module
  import executor
  from executor import *
  
  import io
  import evaluator
  import initializer
  import layers
  import nets
  import optimizer
  import backward
  import regularizer
  from param_attr import ParamAttr
  
  from core import LoDTensor, CPUPlace, GPUPlace
  
  Tensor = LoDTensor
  __all__ = framework.__all__ + executor.__all__ + [
      'io', 'initializer', 'layers', 'nets', 'optimizer', 'backward',
      'regularizer', 'LoDTensor', 'CPUPlace', 'GPUPlace', 'Tensor', 'ParamAttr'
  ]
  
  
  def __read_gflags_from_env__():
      """
      Enable reading gflags from environment variables.
      
      Returns:
          None
      """
      import sys
      import core
      read_env_flags = ['use_pinned_memory']
      if core.is_compile_gpu():
          read_env_flags.append('fraction_of_gpu_memory_to_use')
      core.init_gflags([sys.argv[0]] +
                       ["--tryfromenv=" + ",".join(read_env_flags)])
  
  
  __read_gflags_from_env__()
  
subject: Fix python.v2.fluid arg parse (#6055)