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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 prepare_headers(self, http_headers, soap_action):
 """Prepare the http headers for sending. Add the SOAPACTION header to the others. Args: http_headers (dict):
 A dict in the form {'Header': 'Value,..} containing http headers to use for the http request. soap_action (str):
 The value of the SOAPACTION header. Returns: dict: headers including the SOAPACTION header. """


        headers = {'Content-Type': 'text/xml; charset="utf-8"'}
        if soap_action is not None:
            headers.update({'SOAPACTION': '"{}"'.format(soap_action)})
        if http_headers is not None:
            headers.update(http_headers)
        return headers