class_docstr: Parser for command line arguments and ini-file values.
  
  :ivar extra_info: dict of generic param -> value to display in case
      there's an error processing the command line arguments.
code: def __init__(self, usage=None, processopt=None):
      self._anonymous = OptionGroup("custom options", parser=self)
      self._groups = []
      self._processopt = processopt
      self._usage = usage
      self._inidict = {}
      self._ininames = []
      self.extra_info = {}
  
imports: import argparse
  import warnings
  import py
  import six
  from _pytest.config.exceptions import UsageError
label_desc: Use image node_id 1 to create a new Parser object from inherited base classes: object with example: obj = Parser(usage, processopt)