parameters: (
      req,  # type: InstallRequirement
      output_dir,  # type: str
      verify,  # type: bool
      build_options,  # type: List[str]
      global_options,  # type: List[str]
  )
return_statement: return wheel_path
docstring: Build one wheel.
  
      :return: The filename of the built wheel, or None if the build failed.
docstring_summary: Build one wheel.
docstring_tokens: Build one wheel .
function: def _build_one(
      req,  # type: InstallRequirement
      output_dir,  # type: str
      verify,  # type: bool
      build_options,  # type: List[str]
      global_options,  # type: List[str]
  ):
      # type: (...) -> Optional[str]
      """Build one wheel.
  
      :return: The filename of the built wheel, or None if the build failed.
      """
      try:
          ensure_dir(output_dir)
      except OSError as e:
          logger.warning(
              "Building wheel for %s failed: %s",
              req.name, e,
          )
          return None
  
      # Install build deps into temporary directory (PEP 518)
      with req.build_env:
          wheel_path = _build_one_inside_env(
              req, output_dir, build_options, global_options
          )
      if wheel_path and verify:
          try:
              _verify_one(req, wheel_path)
          except (InvalidWheelFilename, UnsupportedWheel) as e:
              logger.warning("Built wheel for %s is invalid: %s", req.name, e)
              return None
      return wheel_path
function_tokens: def _build_one ( req , # type: InstallRequirement output_dir , # type: str verify , # type: bool build_options , # type: List[str] global_options , # type: List[str] ) : # type: (...) -> Optional[str] try : ensure_dir ( output_dir ) except OSError as e : logger . warning ( "Building wheel for %s failed: %s" , req . name , e , ) return None # Install build deps into temporary directory (PEP 518) with req . build_env : wheel_path = _build_one_inside_env ( req , output_dir , build_options , global_options ) if wheel_path and verify : try : _verify_one ( req , wheel_path ) except ( InvalidWheelFilename , UnsupportedWheel ) as e : logger . warning ( "Built wheel for %s is invalid: %s" , req . name , e ) return None return wheel_path