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##### SUMMARY
<!--- Describe the new feature/improvement briefly below -->
This feature would implement a ClearSessions command for the Sessions category of redfish_command, to clear all active sessions.

##### ISSUE TYPE
- Feature Idea

##### COMPONENT NAME
<!--- Write the short name of the module, plugin, task or feature below, use your best guess if unsure -->
redfish_command.py
redfish_utils.py

##### ADDITIONAL INFORMATION
<!--- Describe how the feature would be used, why it is needed and what it would solve -->
This command would help user to clear all active sessions.

<!--- Paste example playbooks or commands between quotes below -->
```yaml

```

<!--- HINT: You can also paste gist.github.com links for larger files -->

for m in memory_list:
            dimm = {}
            uri = self.root_uri + m
            response = self.get_request(uri)
            if response['ret'] is False:
                return response
            data = response['data']
            if "Status" in data:
                if "State" in data["Status"]:
                    if data["Status"]["State"] == "Absent":
                        continue
            else:
                continue
            for property in properties:
                if property in data:
                    dimm[property] = data[property]
            memory_results.append(dimm)
        result["entries"] = memory_results
        return result
    def get_multi_memory_inventory(self):
        return self.aggregate_systems(self.get_memory_inventory)
    def get_nic_inventory(self, resource_uri):
        result = {}
        nic_list = []
        nic_results = []
        key = "EthernetInterfaces"
        
        properties = ['Description', 'FQDN', 'IPv4Addresses', 'IPv6Addresses',
                      'NameServers', 'MACAddress', 'PermanentMACAddress',
                      'SpeedMbps', 'MTUSize', 'AutoNeg', 'Status']