code: def __init__(self, path, overwrite, entry_field, block_size):
      self.path = path
      self.overwrite = overwrite
      self.entry_field = entry_field
      self.block_size = block_size
  
imports: import abc
  import json
  from hail.expr.types import hail_type
  from ..typecheck import typecheck_method, nullable, dictof, sequenceof
  from ..utils.misc import escape_str
  from .export_type import ExportType
label_desc: Use image node_id 1 to create a new MatrixBlockMatrixWriter object from inherited base classes: MatrixWriter with example: obj = MatrixBlockMatrixWriter(path, overwrite, entry_field, block_size)