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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 _request(self, function, params, method='POST', headers={}):
 """Builds a request object."""

        
        if method is 'POST':
            params = urllib.parse.urlencode(params)
            headers = { "Content-type": "application/x-www-form-urlencoded", "Accept": "text/plain" }
        
        path = '/%s/%s' % (self._version, function)
        
        self._conn.request(method, path, params, headers)
        return self._conn.getresponse()