<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def attributes(attrs):
 """Returns an attribute list, constructed from the dictionary attrs. """

    attrs = attrs or {}
    ident = attrs.get("id", "")
    classes = attrs.get("classes", [])
    keyvals = [[x, attrs[x]] for x in attrs if (x != "classes" and x != "id")]
    return [ident, classes, keyvals]