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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 _GetMetadataRequest(self, metadata_url, params=None, timeout=None):
 """Performs a GET request with the metadata headers. Args: metadata_url: string, the URL to perform a GET request on. params: dictionary, the query parameters in the GET request. timeout: int, timeout in seconds for metadata requests. Returns: HTTP response from the GET request. Raises: urlerror.HTTPError: raises when the GET request fails. """

    headers = {'Metadata-Flavor': 'Google'}
    params = urlparse.urlencode(params or {})
    url = '%s?%s' % (metadata_url, params)
    request = urlrequest.Request(url, headers=headers)
    request_opener = urlrequest.build_opener(urlrequest.ProxyHandler({}))
    timeout = timeout or self.timeout
    return request_opener.open(request, timeout=timeout*1.1)