You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: signature.go
    path of file: ./repos/beam/sdks/go/pkg/beam/core/funcx
    
    the code of the file until where you have to start completion: // Licensed to the Apache Software Foundation (ASF) under one or more
// contributor license agreements.  See the NOTICE file distributed with
// this work for additional information regarding copyright ownership.
// The ASF licenses this file to You under the Apache License, Version 2.0
// (the "License"); you may not use this file except in compliance with
// the License.  You may obtain a copy of the License at
//
//    http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITH
    
func Satisfy(fn any, sig *Signature) error {
	var in, out []reflect.Type
	var typ reflect.Type
	switch fx := fn.(type) {
	case *Fn:
		typ = fx.Fn.Type()
	case reflectx.Func:
		typ = fx.Type()
	default:
		value := reflect.ValueOf(fn)
		if value.Kind() != reflect.Func {
			return errors.Errorf("not a function: %v", value)
		}
		typ = value.Type()
	}
	for i := 0; i < typ.NumIn(); i++ {
		in = append(in, typ.In(i))
	}
	for i := 0; i < typ.NumOut(); i++ {
		out = append(out, typ.Out(i))
	}
	if len(in) < len(sig.Args) || len(out) < len(sig.Return) {
		return errors.Errorf("not enough required parameters: %v", typ)
	}

	if len(in) > len(sig.Args)+len(sig.OptArgs) || len(out) > len(sig.Return)+len(sig.OptReturn) {
		return errors.Errorf("too many parameters: %v", typ)
	}

	// (1) Create generic binding. If inconsistent, reject fn. We do not allow
	// optional parameters to be _defining_ generic to avoid ambiguity here.

	m := make(map[string]reflect.Type)
	off := len(in) - len(sig.Args)
	if err := bind(in[off:], sig.Args, m); err != nil {
		return err
	}
	if err := bind(out[:len(sig.Return)], sig.Return, m); err != nil {
		return err
	}

	// (2) Check satisfiability under binding.

	if err := matchReq(in[off:], sig.Args); err != nil {
		return err
	}
	if err := matchOpt(in[:off], sig.OptArgs, m); err != nil {
		return err
	}
	if err := matchReq(out[:len(sig.Return)], sig.Return); err != nil {
		return err
	}
	return matchOpt(out[len(sig.Return):], sig.OptReturn, m)
}