def dependencies(self):
        '''
        Return all dependencies set via "depends" configuration items 
        return list of tuples: (mystep, package, package_step)
        eg: ('prepare', 'gcc', 'install')
        '''
        ret = list()
        try:
            deps = getattr(self, 'depends', None)
        except KeyError:
            return list()
        for dep in string2list(deps):
            mystep, other = dep.split(':')
            pkg,pkg_step = other.split('_',1)
            ret.append((mystep, pkg, pkg_step))
        return ret