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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def find_executable(executable_name):
 """Tries to find executable in PATH environment It uses ``shutil.which`` method in Python3 and ``distutils.spawn.find_executable`` method in Python2.7 to find the absolute path to the 'name' executable. :param executable_name: name of the executable :returns: Returns the absolute path to the executable or None if not found. """

    if six.PY3:
        executable_abs = shutil.which(executable_name)
    else:
        import distutils.spawn
        executable_abs = distutils.spawn.find_executable(executable_name)

    return executable_abs