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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 alias_delete(indices, aliases, hosts=None, body=None, profile=None, source=None):
    '''
    Delete an alias of an index

    indices
        Single or multiple indices separated by comma, use _all to perform the operation on all indices.
    aliases
        Alias names separated by comma

    CLI example::

        salt myminion elasticsearch.alias_delete testindex_v1 testindex
    '''
    es = _get_instance(hosts, profile)
    if source and body:
        message = 'Either body or source should be specified but not both.'
        raise SaltInvocationError(message)
    if source:
        body = __salt__['cp.get_file_str'](
                  source,
                  saltenv=__opts__.get('saltenv', 'base'))
    try:
        result = es.indices.delete_alias(index=indices, name=aliases)

        return result.get('acknowledged', False)
    except elasticsearch.exceptions.NotFoundError:
        return True
    except elasticsearch.TransportError as e:
        raise CommandExecutionError("Cannot delete alias {0} in index {1}, server returned code {2} with message {3}".format(aliases, indices, e.status_code, e.error))