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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"
```

pass
            kb = self.get_configured_disk_size(expected_disk_spec)
            
            if kb < diskspec.device.capacityInKB:
                self.module.fail_json(
                    msg="Given disk size is smaller than found (%d < %d). Reducing disks is not allowed." %
                        (kb, diskspec.device.capacityInKB))
            if kb != diskspec.device.capacityInKB or disk_modified:
                diskspec.device.capacityInKB = kb
                self.configspec.deviceChange.append(diskspec)
                self.change_detected = True
    def select_host(self):
        hostsystem = self.cache.get_esx_host(self.params['esxi_hostname'])
        if not hostsystem:
            self.module.fail_json(msg='Failed to find ESX host "%(esxi_hostname)s"' % self.params)
        if hostsystem.runtime.connectionState != 'connected' or hostsystem.runtime.inMaintenanceMode:
            self.module.fail_json(msg='ESXi "%(esxi_hostname)s" is in invalid state or in maintenance mode.' % self.params)
        return hostsystem
    def autoselect_datastore(self):
        datastore = None
        datastores = self.cache.get_all_objs(self.content, [vim.Datastore])
        if datastores is None or len(datastores) == 0:
            self.module.fail_json(msg="Unable to find a datastore list when autoselecting")
        datastore_freespace = 0
        for ds in datastores:
            if ds.summary.freeSpace > datastore_freespace:
                datastore = ds
                datastore_freespace = ds.summary.freeSpace
        return datastore
    def get_recommended_datastore(self, datastore_cluster_obj=None):