'Set the CORS (Cross-Origin Resource Sharing) for a bucket.
:type cors_xml: str
:param cors_xml: The XML document describing your desired
CORS configuration.  See the S3 documentation for details
of the exact syntax required.'

def set_cors_xml(self, cors_xml, headers=None):

    fp = StringIO(cors_xml)
    md5 = boto.utils.compute_md5(fp)
    if (headers is None):
        headers = {}
    headers['Content-MD5'] = md5[1]
    headers['Content-Type'] = 'text/xml'
    response = self.connection.make_request('PUT', self.name, data=fp.getvalue(), query_args='cors', headers=headers)
    body = response.read()
    if (response.status == 200):
        return True
    else:
        raise self.connection.provider.storage_response_error(response.status, response.reason, body)
