'Creates a volume.
Can optionally return a Dictionary of changes to the volume object to
be persisted.
If volume_type extra specs includes
\'capabilities:replication <is> True\' the driver
needs to create a volume replica (secondary), and setup replication
between the newly created volume and the secondary volume.
Returned dictionary should include:
.. code-block:: python
volume[\'replication_status\'] = \'copying\'
volume[\'replication_extended_status\'] = <driver specific value>
volume[\'driver_data\'] = <driver specific value>'

@abc.abstractmethod
def create_volume(self, volume):

    return
