isinstance with string representing types Question: isinstance("my string", "str | int") isinstance("my string", "list") Is there a way to check the type of a variable ("my string" in this case) based on a valid type which is stored as a string? I don’t need to import the type, I know it’s builtin (int / str …
Checking if an object is in a determined class python Question: I’m trying to create a class representing vectors (called Vector) and one representing matrices (called Matrix). The problem arised in defining the matrix-vector product: I don’t see errors in the actual implementation, but I tried to add a check before the code to raise …
Faking whether an object is an Instance of a Class in Python Question: Suppose I have a class FakePerson which imitates all the attributes and functionality of a base class RealPerson without extending it. In Python 3, is it possible to fake isinstance() in order to recognise FakePerson as a RealPerson object by only modifying …
collections.Iterable vs typing.Iterable in type annotation and checking for Iterable Question: I found that in Python both collections.Iterable and typing.Iterable can be used in type annotation and checking for whether an object is iterable, i.e., both isinstance(obj, collections.Iterable) and isinstance(obj, typing.Iterable) works. My question is, what are the differences among them? And which one is …
Comparing boolean and int using isinstance Question: Can someone give me an explanation why isinstance() returns True in the following case? I expected False, when writing the code. print isinstance(True, (float, int)) True My guess would be that its Python’s internal subclassing, as zero and one – whether float or int – both evaluate when …
Python check if variable isinstance of any type in list Question: How do I compactly perform the following: var = 7.0 var_is_good = ( isinstance(var, classinfo1) or isinstance(var, classinfo2) or isinstance(var, classinfo3) ) Asked By: D Adams || Source Answers: You were pretty close with the title of your question already. You could use any …
What type are file objects in Python? Question: How can I use isinstance to determine the ‘type’ of a file object, such as in the expression: >>> open(file) Asked By: Aleeee || Source Answers: In Python 3.x, normal file objects are of type io.TextIOWrapper: >>> type(open(‘file.txt’)) <class ‘_io.TextIOWrapper’> >>> from io import TextIOWrapper >>> isinstance(open(‘file.txt’), …
Negative form of isinstance() in Python Question: How would I use a negative form of Python’s isinstance()? Normally negation would work something like x != 1 if x not in y if not a I just haven’t seen an example with isinstance(), so I’d like to know if there’s a correct way to used negation …
How to check if an object is an instance of a namedtuple? Question: How do I check if an object is an instance of a Named tuple? Asked By: Sridhar Ratnakumar || Source Answers: Calling the function collections.namedtuple gives you a new type that’s a subclass of tuple (and no other classes) with a member …
