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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_samples(self, md5='', sha1='', sha256=''):
 """ Searches for a sample in CRITs. Currently only hashes allowed. Args: md5: md5sum sha1: sha1sum sha256: sha256sum Returns: JSON response or None if not found """

        params = {'api_key': self.api_key, 'username': self.username}
        if md5:
            params['c-md5'] = md5
        if sha1:
            params['c-sha1'] = sha1
        if sha256:
            params['c-sha256'] = sha256
        r = requests.get('{0}/samples/'.format(self.url),
                         params=params,
                         verify=self.verify,
                         proxies=self.proxies)
        if r.status_code == 200:
            result_data = json.loads(r.text)
            if 'meta' in result_data:
                if 'total_count' in result_data['meta']:
                    if result_data['meta']['total_count'] > 0:
                        return result_data
        else:
            log.error('Non-200 status code: {}'.format(r.status_code))
        return None