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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 build_dict_to_sign(self, request, signature_headers):
 """Build a dict with headers and values used in the signature. "signature_headers" is a list of lowercase header names. """

        d = {}
        for header in signature_headers:
            if header == '(request-target)':
                continue
            d[header] = request.META.get(self.header_canonical(header))
        return d