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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 execute(self, uri, namespace, action, timeout=2, **kwargs):
 """Executes a given action with optional arguments. The execution of an action of an UPnP/TR64 device needs more than just the name of an action. It needs the control URI which is called to place the action and also the namespace aka service type is needed. The namespace defines the scope or service type of the given action, the same action name can appear in different namespaces. The way how to obtain the needed information's is either through the documentation of the vendor of the device. Or through a discovery requests which return's the URL to the root device description XML. :param str uri: the control URI, for example ``/upnp/control/hosts`` :param str namespace: the namespace for the given action, for example ``urn:dslforum-org:service:Hosts:1`` :param str action: the name of the action to call, for example ``GetGenericHostEntry`` :param float timeout: the timeout to wait for the action to be executed :param kwargs: optional arguments for the given action, depends if the action needs parameter. The arguments are given as dict where the key is the parameter name and the value the value of the parameter. :type kwargs: dict[str, str] :return: returns the results of the action, if any. The results are structured as dict where the key is the name of the result argument and the value is the value of the result. :rtype: dict[str,str] :raises ValueError: if parameters are not set correctly :raises requests.exceptions.ConnectionError: when the action can not be placed on the device :raises requests.exceptions.ConnectTimeout: when download time out Example: :: device.execute("/upnp/control/hosts", "urn:dslforum-org:service:Hosts:1", "GetGenericHostEntry", {"NewIndex": 1}) {'NewActive': '0', 'NewIPAddress': '192.168.0.23', 'NewMACAddress': '9C:20:7B:E7:FF:5F', 'NewInterfaceType': 'Ethernet', 'NewHostName': 'Apple-TV', 'NewAddressSource': 'DHCP', 'NewLeaseTimeRemaining': '0'} .. seealso:: `Additional short explanation of the UPnP protocol <http://www.upnp-hacks.org/upnp.html>`_ :class:`~simpletr64.Discover`, :meth:`~simpletr64.DeviceTR64.loadDeviceDefinitions`, :meth:`~simpletr64.DeviceTR64.loadSCPD` """


        if not uri:
            raise ValueError("No action URI has been defined.")

        if not namespace:
            raise ValueError("No namespace has been defined.")

        if not action:
            raise ValueError("No action has been defined.")

        # soap headers
        header = {'Content-Type': 'text/xml; charset="UTF-8"',
                  'Soapaction': '"' + namespace + "#" + action + '"'}

        # build SOAP body
        body = '''<?xml version="1.0" encoding="UTF-8"?>
<s:Envelope
    s:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/"
    xmlns:s="http://schemas.xmlsoap.org/soap/envelope/"
    xmlns:xsd="http://www.w3.org/2001/XMLSchema"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
    <s:Header/>
    <s:Body>\n'''

        body += "        <u:" + action + ' xmlns="' + namespace + '">\n'

        arguments = {}

        for key in kwargs.keys():
            body += "            <" + key + ">" + str(kwargs[key]) + "</" + key + ">\n"
            arguments[key] = str(kwargs[key])

        body += "        </u:" + action + ">\n"
        body += '''</s:Body>
</s:Envelope>'''

        # setup proxies
        proxies = {}
        if self.__httpsProxy:
            proxies = {"https": self.__httpsProxy}

        if self.__httpProxy:
            proxies = {"http": self.__httpProxy}

        # setup authentication
        auth = None
        if self.__password:
            auth = HTTPDigestAuth(self.__username, self.__password)

        # build the URL
        location = self.__protocol + "://" + self.__hostname + ":" + str(self.port) + uri

        # Post http request
        request = requests.post(location, data=body, headers=header, auth=auth, proxies=proxies, timeout=float(timeout),
                               verify=self.__verify)

        if request.status_code != 200:
            errorStr = DeviceTR64._extractErrorString(request)
            raise ValueError('Could not execute "' + action + str(arguments) + '": ' + str(request.status_code) +
                             ' - ' + request.reason + " -- " + errorStr)

        # parse XML return
        try:
            root = ET.fromstring(request.text.encode('utf-8'))
        except Exception as e:
            raise ValueError("Can not parse results for the action: " + str(e))

        # iterate in the XML structure to get the action result
        actionNode = root[0][0]

        # we need to remove XML namespace for the action node
        namespaceLength = len(namespace) + 2  # add braces
        tag = actionNode.tag[namespaceLength:]

        if tag != (action + "Response"):
            raise ValueError('Soap result structure is wrong, expected action "' + action +
                             'Response" got "' + tag + '".')

        # pack all the received results
        results = {}

        for resultNode in actionNode:
            results[resultNode.tag] = resultNode.text

        return results