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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 sign_direct(self, request, authheaders, secret):
 """Signs a request directly with an appropriate signature. The request's Authorization header will change. Keyword arguments: request -- A request object which can be consumed by this API. authheaders -- A string-indexable object which contains the headers appropriate for this signature version. secret -- The base64-encoded secret key for the HMAC authorization. """

        sig = self.sign(request, authheaders, secret)
        return request.with_header("Authorization", "Acquia {0}:{1}".format(authheaders["id"], sig))