'Parses any child <param> tags in to a dictionary suitable for persistence.
:param parent: Parent element in which to find child <param> tags.
:type parent: ``xml.etree.ElementTree.Element``
:returns: dict'

def __get_params(self, parent):

    rval = {}
    for param in parent.findall('param'):
        key = param.get('id')
        if (key in ['container', 'container_override']):
            from galaxy.tools.deps import requirements
            containers = map(requirements.container_from_element, list(param))
            param_value = map((lambda c: c.to_dict()), containers)
        else:
            param_value = param.text
        if ('from_environ' in param.attrib):
            environ_var = param.attrib['from_environ']
            param_value = os.environ.get(environ_var, param_value)
        elif ('from_config' in param.attrib):
            config_val = param.attrib['from_config']
            param_value = self.app.config.config_dict.get(config_val, param_value)
        rval[key] = param_value
    return rval
