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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 deprecated(instructions):
 """ Flags a method as deprecated. :param instructions: A human-friendly string of instructions, such as: 'Please migrate to add_proxy() ASAP.' :return: DeprecatedWarning """

    def decorator(func):
        """This is a decorator which can be used to mark functions as deprecated.

        It will result in a warning being emitted when the function is used.
        """
        @functools.wraps(func)
        def wrapper(*args, **kwargs):
            message = 'Call to deprecated function {}. {}'.format(func.__name__,
                                                                  instructions)
            frame = inspect.currentframe().f_back
            warnings.warn_explicit(message,
                                   category=DeprecatedWarning,
                                   filename=inspect.getfile(frame.f_code),
                                   lineno=frame.f_lineno)
            return func(*args, **kwargs)
        return wrapper
    return decorator