<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def type_param(self, node, ct):
 """Resolve the type of a leaf or leaf-list node for JSON. """

        types = self.get_types(node)
        ftyp = types[0]
        if len(types) == 1:
            if ftyp in type_class:
                jtyp = type_class[ftyp]
            else:
                jtyp = "other"
            self.xsl_withparam("type", jtyp, ct)
        elif ftyp in ["string", "enumeration", "bits", "binary",
                      "identityref", "instance-identifier"]:
            self.xsl_withparam("type", "string", ct)
        else:
            opts = []
            for t in types:
                if t in union_class:
                    ut = union_class[t]
                elif t in ["int64", "uint64"] or t.startswith("decimal@"):
                    ut = t
                else:
                    ut = "other"
                if ut not in opts:
                    opts.append(ut)
                    if ut == "other": break
                    if ut == "decimal" and "integer" not in opts:
                        opts.append("integer")
            self.xsl_withparam("type", "union", ct)
            self.xsl_withparam("options", ",".join(opts) + ",", ct)