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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
```
""" This class gets datastores """
    def __init__(self, module):
        super(PyVmomiHelper, self).__init__(module)
        self.cache = PyVmomiCache(self.content, dc_name=self.params['datacenter'])
    def lookup_datastore(self, confine_to_datacenter):
        """ Get datastore(s) per ESXi host or vCenter server """
        datastores = self.cache.get_all_objs(self.content, [vim.Datastore], confine_to_datacenter)
        return datastores
    def lookup_datastore_by_cluster(self):
        """ Get datastore(s) per cluster """
        cluster = find_cluster_by_name(self.content, self.params['cluster'])
        if not cluster:
            self.module.fail_json(msg='Failed to find cluster "%(cluster)s"' % self.params)
        c_dc = cluster.datastore
        return c_dc
def main():