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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 get_data_id_by_slug(self, slug):
 """Find data object ID for given slug. This method queries the Resolwe API and requires network access. """

        resolwe_host = os.environ.get('RESOLWE_HOST_URL')
        url = urllib.parse.urljoin(resolwe_host, '/api/data?slug={}&fields=id'.format(slug))

        with urllib.request.urlopen(url, timeout=60) as f:
            data = json.loads(f.read().decode('utf-8'))

        if len(data) == 1:
            return data[0]['id']
        elif not data:
            raise ValueError('Data not found for slug {}'.format(slug))
        else:
            raise ValueError('More than one data object returned for slug {}'.format(slug))