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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 _UpdateEtag(self, response):
 """Update the etag from an API response. Args: response: HTTP response with a header field. Returns: bool, True if the etag in the response header updated. """

    etag = response.headers.get('etag', self.etag)
    etag_updated = self.etag != etag
    self.etag = etag
    return etag_updated