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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def to_json(obj, pretty=False):
 """Converts an object to JSON, using the defaults specified in register_json_default. :obj: the object to convert to JSON :pretty: if True, extra whitespace is added to make the output easier to read """

  sort_keys = False
  indent = None
  separators = (",", ":")

  if isinstance(pretty, tuple):
    sort_keys, indent, separators = pretty
  elif pretty is True:
    sort_keys = True
    indent = 2
    separators = (", ", ": ")

  return json.dumps(obj, sort_keys=sort_keys, indent=indent, separators=separators,
                    default=json_default)