class_docstr: A PClass is a python class with a fixed set of specified fields. PClasses are declared as python classes inheriting
  from PClass. It is defined the same way that PRecords are and behaves like a PRecord in all aspects except that it
  is not a PMap and hence not a collection but rather a plain Python object.
  
  
  More documentation and examples of PClass usage is available at https://github.com/tobgu/pyrsistent
code: def __delattr__(self, key):
      raise AttributeError(
          "Can't delete attribute, key={0}, use remove()".format(key)
      )
  
imports: from pyrsistent._checked_types import InvariantException, CheckedType, _restore_pickle, store_invariants
  from pyrsistent._field_common import set_fields, check_type, is_field_ignore_extra_complaint, PFIELD_NO_INITIAL, serialize, check_global_invariants
  from pyrsistent._transformations import transform
label_desc: Use image node_id 10 for calling the PClass obj's underlying member method code with example usage: obj.__delattr__(key) without return types