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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 a v2 signature. The request's Authorization header will change. This function may also add the required X-Authorization-Timestamp and X-Authorization-Content-SHA256 headers. 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. """

        if request.get_header('x-authorization-timestamp') == '':
            request.with_header("X-Authorization-Timestamp", str(time.time()))
        if request.body is not None and request.body != b'':
            if request.get_header("x-authorization-content-sha256") == '':
                sha256 = hashlib.sha256()
                sha256.update(request.body)
                request.with_header("X-Authorization-Content-SHA256", base64.b64encode(sha256.digest()).decode('utf-8'))
        sig = self.sign(request, authheaders, secret)
        authheaders["signature"] = sig
        return request.with_header("Authorization", "acquia-http-hmac {0}".format(self.unroll_auth_headers(authheaders)))