code: def _encode_base64(s, maxlinelength=60):
      maxbinsize = (maxlinelength // 4) * 3
      pieces = []
      for i in range(0, len(s), maxbinsize):
          chunk = s[i : i + maxbinsize]
          pieces.append(binascii.b2a_base64(chunk))
      return b"        ".join(pieces)
  
file_path: cpython/Mac/Tools/plistlib_generate_testdata.py
imports: from Cocoa import NSMutableDictionary, NSMutableArray, NSString, NSDate, NSNumber
  from Cocoa import NSPropertyListSerialization, NSPropertyListOpenStepFormat
  from Cocoa import NSPropertyListXMLFormat_v1_0, NSPropertyListBinaryFormat_v1_0
  from Cocoa import CFUUIDCreateFromString, NSNull, NSUUID, CFPropertyListCreateData
  from Cocoa import NSURL
  from Cocoa import NSKeyedArchiver
  import datetime
  from collections import OrderedDict
  import binascii
label_desc: Use image node_id 3 for calling a global function with example usage: _encode_base64(s, maxlinelength) and returns: bytes