code: def validity_buffer_from_mask(
      validity_buff: BufferObject,
      validity_dtype: Dtype,
      describe_null: ColumnNullType,
      length: int,
      offset: int = 0,
      allow_copy: bool = True,
  ) -> pa.Buffer:
      """
      Build a PyArrow buffer from the passed mask buffer.
  
      Parameters
      ----------
      validity_buff : BufferObject
          Tuple of underlying validity buffer and associated dtype.
      validity_dtype : Dtype
          Dtype description as a tuple ``(kind, bit-width, format string,
          endianness)``.
      describe_null : ColumnNullType
          Null representation the column dtype uses,
          as a tuple ``(kind, value)``
      length : int
          The number of values in the array.
      offset : int, default: 0
          Number of elements to offset from the start of the buffer.
      allow_copy : bool, default: True
          Whether to allow copying the memory to perform the conversion
          (if false then zero-copy approach is requested).
  
      Returns
      -------
      pa.Buffer
      """
      null_kind, sentinel_val = describe_null
      validity_kind, _, _, _ = validity_dtype
      assert validity_kind == DtypeKind.BOOL
  
      if null_kind == ColumnNullType.NON_NULLABLE:
          # Sliced array can have a NON_NULLABLE ColumnNullType due
          # to no missing values in that slice of an array though the bitmask
          # exists and validity_buff must be set to None in this case
          return None
  
      elif null_kind == ColumnNullType.USE_BYTEMASK or (
          null_kind == ColumnNullType.USE_BITMASK and sentinel_val == 1
      ):
          buff = pa.foreign_buffer(
              validity_buff.ptr,
              validity_buff.bufsize,
              base=validity_buff,
          )
  
          if null_kind == ColumnNullType.USE_BYTEMASK:
              if not allow_copy:
                  raise RuntimeError(
                      "To create a bitmask a copy of the data is "
                      "required which is forbidden by allow_copy=False"
                  )
              mask = pa.Array.from_buffers(
                  pa.int8(), length, [None, buff], offset=offset
              )
              mask_bool = pc.cast(mask, pa.bool_())
          else:
              mask_bool = pa.Array.from_buffers(
                  pa.bool_(), length, [None, buff], offset=offset
              )
  
          if sentinel_val == 1:
              mask_bool = pc.invert(mask_bool)
  
          return mask_bool.buffers()[1]
  
      elif (
          null_kind == ColumnNullType.USE_BITMASK and sentinel_val == 0
      ):
          return pa.foreign_buffer(
              validity_buff.ptr,
              validity_buff.bufsize,
              base=validity_buff,
          )
      else:
          raise NotImplementedError(
              f"{describe_null} null representation is not yet supported."
          )
  
file_path: arrow/python/pyarrow/interchange/from_dataframe.py
imports: from __future__ import annotations
  from typing import Any, Tuple
  from pyarrow.interchange.column import DtypeKind, ColumnBuffers, ColumnNullType
  import pyarrow
  import re
  import pyarrow.compute
  from pyarrow.interchange.column import Dtype
label_desc: Use image node_id 10 for calling a global function with example usage: validity_buffer_from_mask(validity_buff, validity_dtype, describe_null, length, offset, allow_copy) and returns: None, mask_bool, pa