class_docstr: Check for availability of headers and libraries of FFTW and MPI.
  
  :param compiler:
  
      Distutils.ccompiler; The compiler should be the compiler that
      is used for actual compilation to ensure that include
      directories, linker flags etc. are identical.
code: def openmp_linker_flag(self):
      # gcc and newer clang support openmp
      if self.compiler.compiler_type == "unix":
          return "-fopenmp"
      # TODO support other compilers
      else:
          return ""
  
imports: from setuptools import setup, Command
  from setuptools.command.build_ext import build_ext
  from sysconfig import get_platform
  from contextlib import redirect_stderr, redirect_stdout
  import os
  import logging
  import platform
  import sys
  import versioneer
label_desc: Use image node_id 11 for calling the EnvironmentSniffer obj's underlying member method code with example usage: obj.openmp_linker_flag() and returns: str, str