<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:

def upgrade_tools_all(call=None):
    '''
    To upgrade VMware Tools on all virtual machines present in
    the specified provider

    .. note::

        If the virtual machine is running Windows OS, this function
        will attempt to suppress the automatic reboot caused by a
        VMware Tools upgrade.

    CLI Example:

    .. code-block:: bash

        salt-cloud -f upgrade_tools_all my-vmware-config
    '''
    if call != 'function':
        raise SaltCloudSystemExit(
            'The upgrade_tools_all function must be called with '
            '-f or --function.'
        )

    ret = {}
    vm_properties = ["name"]

    vm_list = salt.utils.vmware.get_mors_with_properties(_get_si(), vim.VirtualMachine, vm_properties)

    for vm in vm_list:
        ret[vm['name']] = _upg_tools_helper(vm['object'])

    return ret