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##### SUMMARY
<!--- Explain the problem briefly below -->
vmware_guest throws error that vmdk already exists although it does not. It is created during running the module but somehow fails. 

pyvmomi-6.7.1.2018.12

##### ISSUE TYPE
- Bug Report

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

##### ANSIBLE VERSION
<!--- Paste verbatim output from "ansible --version" between quotes -->
```paste below
2.8.1
```

##### STEPS TO REPRODUCE
<!--- Describe exactly how to reproduce the problem, using a minimal test-case -->

<!--- Paste example playbooks or commands between quotes below -->
```yaml
- name: Create new VM
  vmware_guest:
    hostname: "{{ vcenter_hostname }}"
    esxi_hostname: "{{ esxi_host }}"
    username: '{{domain_user}}'
    password: "{{ domain_user_password }}"
    validate_certs: False
    datacenter: TM
    name: "{{ vm_hostname }}"
    folder: "{{ vm_destination }}"      
    state: poweredon
    disk:
    - size_gb: '{{ disk_size }}'
      type: thin
      autoselect_datastore: True
    hardware:
      memory_mb: "{{ memory }}"
      num_cpus: "{{ cores }}"
      num_cpu_cores_per_socket: "{{ cores }}"
    networks:
    - name: LAN
      domain: "{{ domain }}"
      dns_servers:
      -  "{{ dns1 }}"
      -  "{{ dns2 }}"
      type: static
      ip: "{{ ip }}"
      netmask: 255.255.254.0
      gateway: 192.168.1.5
    customization:
      autologon: True
      hostname: "{{ vm_hostname }}"
      domain: "{{ domain }}"
      password: vagrant
      domainadmin: "{{ domain_user }}"
      domainadminpassword: "{{ domain_user_password }}"
      joindomain: "{{ domain }}"
      timezone: 105
      runonce:
      - powershell.exe -ExecutionPolicy Unrestricted -File C:\StartupScripts\ConfigureRemotingForAnsible.ps1 -ForceNewSSLCert -EnableCredSSP
      - powershell.exe -ExecutionPolicy Unrestricted -File C:\StartupScripts\DisableFirewall.ps1 
    wait_for_customization: yes
    template: "{{ vm_template }}"
    wait_for_ip_address: yes
```

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

##### EXPECTED RESULTS
<!--- Describe what you expected to happen when running the steps above -->
Should just create the VM.

##### ACTUAL RESULTS
<!--- Describe what actually happened. If possible run with extra verbosity (-vvvv) -->

<!--- Paste verbatim command output between quotes -->
```paste below
Failed to create a virtual machine : Cannot complete the operation because the file or folder [EL02] ********/********.vmdk already exists"
```

datastore_cluster = self.cache.find_obj(self.content, [vim.StoragePod], datastore_name)
                if datastore_cluster:
                    
                    datastore_name = self.get_recommended_datastore(datastore_cluster_obj=datastore_cluster)
                
                datastore = self.cache.find_obj(self.content, [vim.Datastore], datastore_name)
            else:
                self.module.fail_json(msg="Either datastore or autoselect_datastore should be provided to select datastore")
        if not datastore and self.params['template']:
            
            disks = [x for x in vm_obj.config.hardware.device if isinstance(x, vim.vm.device.VirtualDisk)]
            if disks:
                datastore = disks[0].backing.datastore
                datastore_name = datastore.name
            
            if datastore:
                dc = self.cache.get_parent_datacenter(datastore)
                if dc.name != self.params['datacenter']:
                    datastore = self.autoselect_datastore()
                    datastore_name = datastore.name
        if not datastore:
            if len(self.params['disk']) != 0 or self.params['template'] is None:
                self.module.fail_json(msg="Unable to find the datastore with given parameters."
                                          " This could mean, %s is a non-existent virtual machine and module tried to"
                                          " deploy it as new virtual machine with no disk. Please specify disks parameter"
                                          " or specify template to clone from." % self.params['name'])
            self.module.fail_json(msg="Failed to find a matching datastore")
        return datastore, datastore_name
    def obj_has_parent(self, obj, parent):