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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 generate_signed_url( self, expiration=None, api_access_endpoint=_API_ACCESS_ENDPOINT, method="GET", content_md5=None, content_type=None, response_disposition=None, response_type=None, generation=None, headers=None, query_parameters=None, client=None, credentials=None, version=None, ):
 """Generates a signed URL for this blob. .. note:: If you are on Google Compute Engine, you can't generate a signed URL using GCE service account. Follow `Issue 50`_ for updates on this. If you'd like to be able to generate a signed URL from GCE, you can use a standard service account from a JSON file rather than a GCE service account. .. _Issue 50: https://github.com/GoogleCloudPlatform/\ google-auth-library-python/issues/50 If you have a blob that you want to allow access to for a set amount of time, you can use this method to generate a URL that is only valid within a certain time period. This is particularly useful if you don't want publicly accessible blobs, but don't want to require users to explicitly log in. :type expiration: Union[Integer, datetime.datetime, datetime.timedelta] :param expiration: Point in time when the signed URL should expire. :type api_access_endpoint: str :param api_access_endpoint: Optional URI base. :type method: str :param method: The HTTP verb that will be used when requesting the URL. :type content_md5: str :param content_md5: (Optional) The MD5 hash of the object referenced by ``resource``. :type content_type: str :param content_type: (Optional) The content type of the object referenced by ``resource``. :type response_disposition: str :param response_disposition: (Optional) Content disposition of responses to requests for the signed URL. For example, to enable the signed URL to initiate a file of ``blog.png``, use the value ``'attachment; filename=blob.png'``. :type response_type: str :param response_type: (Optional) Content type of responses to requests for the signed URL. Used to over-ride the content type of the underlying blob/object. :type generation: str :param generation: (Optional) A value that indicates which generation of the resource to fetch. :type headers: dict :param headers: (Optional) Additional HTTP headers to be included as part of the signed URLs. See: https://cloud.google.com/storage/docs/xml-api/reference-headers Requests using the signed URL *must* pass the specified header (name and value) with each request for the URL. :type query_parameters: dict :param query_parameters: (Optional) Additional query paramtersto be included as part of the signed URLs. See: https://cloud.google.com/storage/docs/xml-api/reference-headers#query :type client: :class:`~google.cloud.storage.client.Client` or ``NoneType`` :param client: (Optional) The client to use. If not passed, falls back to the ``client`` stored on the blob's bucket. :type credentials: :class:`oauth2client.client.OAuth2Credentials` or :class:`NoneType` :param credentials: (Optional) The OAuth2 credentials to use to sign the URL. Defaults to the credentials stored on the client used. :type version: str :param version: (Optional) The version of signed credential to create. Must be one of 'v2' | 'v4'. :raises: :exc:`ValueError` when version is invalid. :raises: :exc:`TypeError` when expiration is not a valid type. :raises: :exc:`AttributeError` if credentials is not an instance of :class:`google.auth.credentials.Signing`. :rtype: str :returns: A signed URL you can use to access the resource until expiration. """

        if version is None:
            version = "v2"
        elif version not in ("v2", "v4"):
            raise ValueError("'version' must be either 'v2' or 'v4'")

        resource = "/{bucket_name}/{quoted_name}".format(
            bucket_name=self.bucket.name, quoted_name=quote(self.name.encode("utf-8"))
        )

        if credentials is None:
            client = self._require_client(client)
            credentials = client._credentials

        if version == "v2":
            helper = generate_signed_url_v2
        else:
            helper = generate_signed_url_v4

        return helper(
            credentials,
            resource=resource,
            expiration=expiration,
            api_access_endpoint=api_access_endpoint,
            method=method.upper(),
            content_md5=content_md5,
            content_type=content_type,
            response_type=response_type,
            response_disposition=response_disposition,
            generation=generation,
            headers=headers,
            query_parameters=query_parameters,
        )