<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def is_executable(value, **kwargs):
 """Indicate whether ``value`` is an executable file. .. caution:: This validator does **NOT** work correctly on a Windows file system. This is due to the vagaries of how Windows manages its file system and the various ways in which it can manage file permission. If called on a Windows file system, this validator will raise :class:`NotImplementedError() <python:NotImplementedError>`. .. caution:: **Use of this validator is an anti-pattern and should be used with caution.** Validating the writability of a file *before* attempting to execute it exposes your code to a bug called `TOCTOU <https://en.wikipedia.org/wiki/Time_of_check_to_time_of_use>`_. This particular class of bug can expose your code to **security vulnerabilities** and so this validator should only be used if you are an advanced user. A better pattern to use when writing to file is to apply the principle of EAFP ("easier to ask forgiveness than permission"), and simply attempt to .. note:: This validator relies on :func:`os.access() <python:os.access>` to check whether ``value`` is writeable. This function has certain limitations, most especially that: * It will **ignore** file-locking (yielding a false-positive) if the file is locked. * It focuses on *local operating system permissions*, which means if trying to access a path over a network you might get a false positive or false negative (because network paths may have more complicated authentication methods). :param value: The value to evaluate. :type value: Path-like object :returns: ``True`` if ``value`` is valid, ``False`` if it is not. :rtype: :class:`bool <python:bool>` :raises NotImplementedError: if called on a Windows system :raises SyntaxError: if ``kwargs`` contains duplicate keyword parameters or duplicates keyword parameters passed to the underlying validator """

    if sys.platform in ['win32', 'cygwin']:
        raise NotImplementedError('not supported on Windows')

    try:
        validators.executable(value,
                              **kwargs)
    except SyntaxError as error:
        raise error
    except Exception:
        return False

    return True