class_docstr: Displays a Qt calendar whose date is specified by a 'format' option.
  
  ============== ========================================================
  **Options:**
  format         Format for displaying the date and converting from a string. Can be any value accepted by
                 `QDate.toString` and `fromString`, or a stringified version of a QDateFormat enum, i.e. 'ISODate',
                 'TextDate' (default), etc.
  ============== ========================================================
code: def _interpretValue(self, v):
      if isinstance(v, str):
          fmt = self._interpretFormat()
          if fmt is None:
              raise ValueError(
                  "Cannot parse date string without a set format"
              )
          v = QtCore.QDate.fromString(v, fmt)
      return v
  
file_path: pyqtgraph/pyqtgraph/parametertree/parameterTypes/calendar.py
imports: from ...Qt import QtCore, QtWidgets
  from ..Parameter import Parameter
  from .basetypes import WidgetParameterItem
label_desc: Use image node_id 3 for calling the CalendarParameter obj's underlying member method code with example usage: obj._interpretValue(v) and returns: v