Not anymore in Python 3.4 which has PEP 3154 and Pickle 4.0 https://www.python.org/dev/peps/pep-3154/ But you need to say you want to use version 4 of the protocol: https://docs.python.org/3/library/pickle.html pickle.dump(d, open(“file”, ‘w’), protocol=4)
r+ is used for reading, and writing mode. b is for binary. r+b mode is open the binary file in read or write mode. You can read more here.
Yes, the fact that it’s a class member is a problem: >>> class Foo(): … Bar = namedtuple(‘Bar’, [‘x’,’y’]) … def baz(self): … b = Foo.Bar(x=2, y=3) … print(type(b)) … >>> a = Foo() >>> a.baz() <class ‘__main__.Bar’> The problem is that when namedtuple() returns a type object, it isn’t aware of the fact that … Read more
Here is a simple workaround for issue 24658. Use pickle.loads or pickle.dumps and break the bytes object into chunks of size 2**31 – 1 to get it in or out of the file. import pickle import os.path file_path = “pkl.pkl” n_bytes = 2**31 max_bytes = 2**31 – 1 data = bytearray(n_bytes) ## write bytes_out = … Read more
When you try to pickle an object, there might be some properties that don’t serialize well. One example of this is an open file handle. Pickle won’t know how to handle the object and will throw an error. You can tell the pickle module how to handle these types of objects natively within a class … Read more
From the docs: Trying to pickle a highly recursive data structure may exceed the maximum recursion depth, a RuntimeError will be raised in this case. You can carefully raise this limit with sys.setrecursionlimit(). Although your trie implementation may be simple, it uses recursion and can lead to issues when converting to a persistent data structure. … Read more
pickling is recursive, not sequential. Thus, to pickle a list, pickle will start to pickle the containing list, then pickle the first element… diving into the first element and pickling dependencies and sub-elements until the first element is serialized. Then moves on to the next element of the list, and so on, until it finally … Read more
This error comes off due to encoding of formerly saved pickle file. If you updated pandas to newly amended version, it produces this import error.
The pickle module implements a fundamental, but powerful algorithm for serializing and de-serializing a Python object structure. Pickling – is the process whereby a Python object hierarchy is converted into a byte stream, and Unpickling – is the inverse operation, whereby a byte stream is converted back into an object hierarchy. Pickling (and unpickling) is … Read more
You should use application/octet-stream.