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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 volume_create(name, size=100, snapshot=None, voltype=None, **kwargs):
    '''
    Create block storage device
    '''
    conn = get_conn()
    create_kwargs = {'name': name,
                     'size': size,
                     'snapshot': snapshot,
                     'voltype': voltype}
    create_kwargs['availability_zone'] = kwargs.get('availability_zone', None)
    return conn.volume_create(**create_kwargs)