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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 sitegate_view(*args_dec, **kwargs_dec):
 """Decorator to mark views used both for signup & sign in."""

    if len(args_dec):  # simple decoration w/o parameters
        return signup_view(signin_view(redirect_signedin(*args_dec, **kwargs_dec)))

    signin = signin_view(**kwargs_dec)
    signup = signup_view(**kwargs_dec)
    return lambda *args, **kwargs: signup(signin(redirect_signedin(*args, **kwargs)))