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marshal

This module contains functions that can read and write Python values in
a binary format. The format is specific to Python, but independent of
machine architecture issues.

Not all Python object types are supported; in general, only objects
whose value is independent from a particular invocation of Python can be
written and read by this module. The following types are supported:
None, integers, floating point numbers, strings, bytes, bytearrays,
tuples, lists, sets, dictionaries, and code objects, where it
should be understood that tuples, lists and dictionaries are only
supported as long as the values contained therein are themselves
supported; and recursive lists and dictionaries should not be written
(they will cause infinite loops).

Variables:

version -- indicates the format that the module uses. Version 0 is the
    historical format, version 1 shares interned strings and version 2
    uses a binary format for floating point numbers.
    Version 3 shares common object references (New in version 3.4).

Functions:

dump() -- write value to a file
load() -- read value from a file
dumps() -- marshal value as a bytes object
loads() -- read value from a bytes-like object

Functions

dump

dump(value, file, version=4, /)

  Write the value on the open file.

    value
      Must be a supported type.
    file
      Must be a writeable binary file.
    version
      Indicates the data format that dump should use.

  If the value has (or contains an object that has) an unsupported type, a
  ValueError exception is raised - but garbage data will also be written
  to the file. The object will not be properly read back by load().

dumps

dumps(value, version=4, /)

  Return the bytes object that would be written to a file by dump(value, file).

    value
      Must be a supported type.
    version
      Indicates the data format that dumps should use.

  Raise a ValueError exception if value has (or contains an object that has) an
  unsupported type.

load

load(file, /)

  Read one value from the open file and return it.

    file
      Must be readable binary file.

  If no valid value is read (e.g. because the data has a different Python
  version's incompatible marshal format), raise EOFError, ValueError or
  TypeError.

  Note: If an object containing an unsupported type was marshalled with
  dump(), load() will substitute None for the unmarshallable type.

loads

loads(bytes, /)

  Convert the bytes-like object to a value.

  If no valid value is found, raise EOFError, ValueError or TypeError.  Extra
  bytes in the input are ignored.

Other members

version = 4