class_docstr: Parser for Elekta data acquisition settings.
  
  This class parses parameters (e.g. events and averaging categories) that
  are defined in the Elekta TRIUX/VectorView data acquisition software (DACQ)
  and stored in ``info['acq_pars']``. It can be used to reaverage raw data
  according to DACQ settings and modify original averaging settings if
  necessary.
  
  Parameters
  ----------
  %(info_not_none)s This is where the DACQ parameters will be taken from.
  
  Attributes
  ----------
  categories : list
      List of averaging categories marked active in DACQ.
  events : list
      List of events that are in use (referenced by some averaging category).
  reject : dict
      Rejection criteria from DACQ that can be used with mne.Epochs.
      Note that mne does not support all DACQ rejection criteria
      (e.g. spike, slope).
  flat : dict
      Flatness rejection criteria from DACQ that can be used with mne.Epochs.
  acq_dict : dict
      All DACQ parameters.
  
  See Also
  --------
  mne.io.Raw.acqparser : Access the parser through a Raw attribute.
  
  Notes
  -----
  Any averaging category (also non-active ones) can be accessed by indexing
  as ``acqparserfif['category_name']``.
docstr: Return an averaging category, or list of categories.
  
  Parameters
  ----------
  item : str | list of str
      Name of the category (comment field in DACQ).
  
  Returns
  -------
  conds : dict | list of dict
      Each dict should have the following keys:
  
      comment: str
          The comment field in DACQ.
      state : bool
          Whether the category was marked enabled in DACQ.
      index : int
          The index of the category in DACQ. Indices start from 1.
      event : int
          DACQ index of the reference event (trigger event, zero time for
          the corresponding epochs). Note that the event indices start
          from 1.
      start : float
          Start time of epoch relative to the reference event.
      end : float
          End time of epoch relative to the reference event.
      reqevent : int
          Index of the required (conditional) event.
      reqwhen : int
          Whether the required event is required before (1) or after (2)
          the reference event.
      reqwithin : float
          The time range within which the required event must occur,
          before or after the reference event.
      display : bool
          Whether the category was displayed online in DACQ.
      nave : int
          Desired number of averages. DACQ stops collecting averages once
          this number is reached.
      subave : int
          Whether to compute normal and alternating subaverages, and
          how many epochs to include. See the Elekta data acquisition
          manual for details. Currently the class does not offer any
          facility for computing subaverages, but it can be done manually
          by the user after collecting the epochs.
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code: def __getitem__(self, item):
      """Return an averaging category, or list of categories.
  
      Parameters
      ----------
      item : str | list of str
          Name of the category (comment field in DACQ).
  
      Returns
      -------
      conds : dict | list of dict
          Each dict should have the following keys:
  
          comment: str
              The comment field in DACQ.
          state : bool
              Whether the category was marked enabled in DACQ.
          index : int
              The index of the category in DACQ. Indices start from 1.
          event : int
              DACQ index of the reference event (trigger event, zero time for
              the corresponding epochs). Note that the event indices start
              from 1.
          start : float
              Start time of epoch relative to the reference event.
          end : float
              End time of epoch relative to the reference event.
          reqevent : int
              Index of the required (conditional) event.
          reqwhen : int
              Whether the required event is required before (1) or after (2)
              the reference event.
          reqwithin : float
              The time range within which the required event must occur,
              before or after the reference event.
          display : bool
              Whether the category was displayed online in DACQ.
          nave : int
              Desired number of averages. DACQ stops collecting averages once
              this number is reached.
          subave : int
              Whether to compute normal and alternating subaverages, and
              how many epochs to include. See the Elekta data acquisition
              manual for details. Currently the class does not offer any
              facility for computing subaverages, but it can be done manually
              by the user after collecting the epochs.
  
      """
      if isinstance(item, str):
          item = [item]
      else:
          _validate_type(item, list, "Keys", "category names")
      cats = list()
      for it in item:
          if it in self._categories:
              cats.append(self._categories[it])
          else:
              raise KeyError("No such category")
      return cats[0] if len(cats) == 1 else cats
  
imports: from collections.abc import Sequence
  from pathlib import Path
  import numpy
  from ._fiff.constants import FIFF
  from ._fiff.open import fiff_open
  from ._fiff.pick import pick_channels
  from ._fiff.tag import read_tag
  from ._fiff.tree import dir_tree_find
  from ._fiff.write import end_block, start_and_end_file, start_block, write_int
  from .utils import _check_fname, _check_integer_or_list, _check_on_missing, _check_option, _get_stim_channel, _on_missing, _pl, _validate_type, check_fname, fill_doc, logger, verbose, warn
label_desc: Use image node_id 3 for calling the AcqParserFIF obj's underlying member method code with example usage: obj.__getitem__(item) and returns: unknown