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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def vm_allocate(call=None, kwargs=None):
    '''
    Allocates a new virtual machine in OpenNebula.

    .. versionadded:: 2016.3.0

    path
        The path to a file defining the template of the VM to allocate.
        Syntax within the file can be the usual attribute=value or XML.
        Can be used instead of ``data``.

    data
        Contains the template definitions of the VM to allocate. Syntax can
        be the usual attribute=value or XML. Can be used instead of ``path``.

    hold
        If this parameter is set to ``True``, the VM will be created in
        the ``HOLD`` state. If not set, the VM is created in the ``PENDING``
        state. Default is ``False``.

    CLI Example:

    .. code-block:: bash

        salt-cloud -f vm_allocate path=/path/to/vm_template.txt
        salt-cloud --function vm_allocate path=/path/to/vm_template.txt hold=True
    '''
    if call != 'function':
        raise SaltCloudSystemExit(
            'The vm_allocate function must be called with -f or --function.'
        )

    if kwargs is None:
        kwargs = {}

    path = kwargs.get('path', None)
    data = kwargs.get('data', None)
    hold = kwargs.get('hold', False)

    if data:
        if path:
            log.warning(
                'Both the \'data\' and \'path\' arguments were provided. '
                '\'data\' will take precedence.'
            )
    elif path:
        with salt.utils.files.fopen(path, mode='r') as rfh:
            data = rfh.read()
    else:
        raise SaltCloudSystemExit(
            'The vm_allocate function requires either \'data\' or a file \'path\' '
            'to be provided.'
        )

    server, user, password = _get_xml_rpc()
    auth = ':'.join([user, password])
    response = server.one.vm.allocate(auth, data, salt.utils.data.is_true(hold))

    ret = {
        'action': 'vm.allocate',
        'allocated': response[0],
        'vm_id': response[1],
        'error_code': response[2],
    }

    return ret