<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def fromxml(node):
 """Static method returning an Action instance from the given XML description. Node can be a string or an etree._Element."""

        if not isinstance(node,ElementTree._Element): #pylint: disable=protected-access
            node = parsexmlstring(node)
        assert node.tag.lower() == 'action'

        kwargs = {}
        args = []
        if 'id' in node.attrib:
            kwargs['id'] = node.attrib['id']
        elif 'name' in node.attrib:
            kwargs['name'] = node.attrib['name']
        elif 'description' in node.attrib:
            kwargs['description'] = node.attrib['description']
        elif 'method' in node.attrib:
            kwargs['method'] = node.attrib['method']
        elif 'mimetype' in node.attrib:
            kwargs['mimetype'] = node.attrib['mimetype']
        elif 'allowanonymous' in node.attrib:
            if node.attrib['allowanonymous'] == "yes":
                kwargs['allowanonymous'] = True

        found = False
        for subnode in node:
            if subnode.tag.lower() == 'parametercondition':
                kwargs[node.tag] = ParameterCondition.fromxml(subnode)
            elif subnode.tag in vars(clam.common.parameters):
                args.append(vars(clam.common.parameters)[subnode.tag].fromxml(subnode))
        if not found:
            raise Exception("No condition found in ParameterCondition!")
        return Action(*args, **kwargs)