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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 cluster_remove(version,
                   name='main',
                   stop=False):
    '''
    Remove a cluster on a Postgres server. By default it doesn't try
    to stop the cluster.

    CLI Example:

    .. code-block:: bash

        salt '*' postgres.cluster_remove '9.3'

        salt '*' postgres.cluster_remove '9.3' 'main'

        salt '*' postgres.cluster_remove '9.3' 'main' stop=True

    '''
    cmd = [salt.utils.path.which('pg_dropcluster')]
    if stop:
        cmd += ['--stop']
    cmd += [version, name]
    cmdstr = ' '.join([pipes.quote(c) for c in cmd])
    ret = __salt__['cmd.run_all'](cmdstr, python_shell=False)
    # FIXME - return Boolean ?
    if ret.get('retcode', 0) != 0:
        log.error('Error removing a Postgresql cluster %s/%s', version, name)
    else:
        ret['changes'] = ('Successfully removed'
                          ' cluster {0}/{1}').format(version, name)
    return ret