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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 start(self, attempts=5, timeout=2):
 """ Start the network, will check if the network is active ``attempts`` times, waiting ``timeout`` between each attempt. Args: attempts (int):
 number of attempts to check the network is active timeout (int):
 timeout for each attempt Returns: None Raises: RuntimeError: if network creation failed, or failed to verify it is active. """


        if not self.alive():
            with LogTask('Create network %s' % self.name()):
                net = self.libvirt_con.networkCreateXML(self._libvirt_xml())
                if net is None:
                    raise RuntimeError(
                        'failed to create network, XML: %s' %
                        (self._libvirt_xml())
                    )
                for _ in range(attempts):
                    if net.isActive():
                        return
                    LOGGER.debug(
                        'waiting for network %s to become active', net.name()
                    )
                    time.sleep(timeout)
                raise RuntimeError(
                    'failed to verify network %s is active' % net.name()
                )