def get_normalized_parameters(self):
        """Return a string that contains the parameters that must be signed."""
        items = []
        for key, value in self.iteritems():
            if key == 'oauth_signature':
                continue
            # 1.0a/9.1.1 states that kvp must be sorted by key, then by value,
            # so we unpack sequence values into multiple items for sorting.
            if isinstance(value, basestring):
                items.append((to_utf8_if_string(key), to_utf8(value)))
            else:
                try:
                    value = list(value)
                except __HOLE__, e:
                    assert 'is not iterable' in str(e)
                    items.append((to_utf8_if_string(key), to_utf8_if_string(value)))
                else:
                    items.extend((to_utf8_if_string(key), to_utf8_if_string(item)) for item in value)

        # Include any query string parameters from the provided URL
        query = urlparse.urlparse(self.url)[4]

        url_items = self._split_url_string(query).items()
        url_items = [(to_utf8(k), to_utf8(v)) for k, v in url_items if k != 'oauth_signature' ]
        items.extend(url_items)

        items.sort()
        encoded_str = urllib.urlencode(items)
        # Encode signature parameters per Oauth Core 1.0 protocol
        # spec draft 7, section 3.6
        # (http://tools.ietf.org/html/draft-hammer-oauth-07#section-3.6)
        # Spaces must be encoded with "%20" instead of "+"
        return encoded_str.replace('+', '%20').replace('%7E', '~')
dataset/ETHPy150Open ibagrak/algae/gae/libs/oauth2/__init__.py/Request.get_normalized_parameters