class_docstr: Parse HOCON files: https://github.com/typesafehub/config/blob/master/HOCON.md
class_docstr_tok: ["Parse","HOCON","files",":","https",":","\/\/github.com\/typesafehub\/config\/blob\/master\/HOCON.md"]
code: def get_supported_period_type_map(cls):
      if cls.supported_period_map is None:
          cls.supported_period_map = {}
          cls.supported_period_map.update(cls.period_type_map)
  
          try:
              from dateutil import relativedelta
  
              if relativedelta is not None:
                  cls.supported_period_map.update(
                      cls.optional_period_type_map
                  )
          except Exception:
              pass
  
      return cls.supported_period_map
  
imports: import itertools
  import re
  import os
  import socket
  import contextlib
  import codecs
  from datetime import timedelta
  from pyparsing import Forward, Keyword, QuotedString, Word, Literal, Suppress, Regex, Optional, SkipTo, ZeroOrMore, Group, lineno, col, TokenConverter, replaceWith, alphanums, alphas8bit, ParseSyntaxException, StringEnd
  from pyparsing import ParserElement
  from .config_tree import ConfigTree, ConfigSubstitution, ConfigList, ConfigValues, ConfigUnquotedString, ConfigInclude, NoneValue, ConfigQuotedString
  from .exceptions import ConfigSubstitutionException, ConfigMissingException, ConfigException
  import logging
  import copy
label_desc: Use image node_id 1 for calling the ConfigParser obj's underlying member method code with example usage: obj.get_supported_period_type_map(cls) and returns: cls