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##### SUMMARY

Two vmware modules uses `copy()` to duplicate an internal instance of a pyvmomi object. This to be able to modify the object during an iteration.

- https://github.com/ansible/ansible/blob/622a493ae03bd5e5cf517d336fc426e9d12208c7/lib/ansible/modules/cloud/vmware/vmware_guest.py#L788
- https://github.com/ansible/ansible/blob/622a493ae03bd5e5cf517d336fc426e9d12208c7/lib/ansible/modules/cloud/vmware/vmware_datastore_facts.py#L220

As explain here, https://github.com/ansible/ansible/pull/60196/files#r312643761 this is not the best approach and this may impact the performance.

##### ISSUE TYPE
- Bug Report

##### COMPONENT NAME

vmware

##### ANSIBLE VERSION
<!--- Paste verbatim output from "ansible --version" between quotes -->
```paste below
devel
```
diskspec = vim.vm.device.VirtualDeviceSpec()
        diskspec.operation = vim.vm.device.VirtualDeviceSpec.Operation.add
        diskspec.device = vim.vm.device.VirtualDisk()
        diskspec.device.backing = vim.vm.device.VirtualDisk.FlatVer2BackingInfo()
        diskspec.device.controllerKey = scsi_ctl.device.key
        if self.next_disk_unit_number == 7:
            raise AssertionError()
        if disk_index == 7:
            raise AssertionError()
        """
        Configure disk unit number.
        """
        if disk_index is not None:
            diskspec.device.unitNumber = disk_index
            self.next_disk_unit_number = disk_index + 1
        else:
            diskspec.device.unitNumber = self.next_disk_unit_number
            self.next_disk_unit_number += 1
        
        if self.next_disk_unit_number == 7:
            self.next_disk_unit_number += 1
        return diskspec
    def get_device(self, device_type, name):