typeerror: isinstance() arg 2 must be a type or tuple of types

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The TypeError: isinstance() arg 2 must be a type or tuple of types error is raised when you pass an invalid argument as the second argument to the isinstance() function. The second argument to isinstance() must be a type (such as int, str, or list) or a tuple of types.

Here are some examples of correct usage of isinstance():

my_var = "hello"

if isinstance(my_var, str):
    print("my_var is a string")
else:
    print("my_var is not a string")

if isinstance(my_var, (int, str)):
    print("my_var is a string or an integer")
else:
    print("my_var is not a string or an integer")

And here are some examples of incorrect usage that would raise the TypeError: isinstance() arg 2 must be a type or tuple of types error:

my_var = "hello"

if isinstance(my_var, "str"):  # incorrect: "str" is a string, not a type
    print("my_var is a string")
else:
    print("my_var is not a string")

if isinstance(my_var, ["str"]):  # incorrect: ["str"] is a list, not a type or tuple of types
    print("my_var is a string")
else:
    print("my_var is not a string")

if isinstance(my_var, {"str"}):  # incorrect: {"str"} is a set, not a type or tuple of types
    print("my_var is a string")
else:
    print("my_var is not a string")

Isinstance() arg 2 must be a type or tuple of types matplotlib

import matplotlib.pyplot as plt

fig, ax = plt.subplots()

if isinstance(ax, plt.Axes):  # TypeError: isinstance() arg 2 must be a type or tuple of types :- in this line error occurred if you not provide second argument correctly  
    print("ax is an Axes object")
else:
    print("ax is not an Axes object")

In this example, we are using isinstance() to check if ax is an instance of the Axes class. Since ax is an Axes object, isinstance() returns True and the code prints “ax is an Axes object”.

TypeError: isinstance() arg 2 must be a type or tuple of types django

In the context of Django, this error might occur if you are trying to use isinstance() to check the type of a Django object, but you pass an invalid type as the second argument.

Here’s an example of how this error might occur in the context of Django:

 from django.db import models

class MyModel(models.Model):
    name = models.CharField(max_length=255)

my_obj = MyModel.objects.create(name="John")

if isinstance(my_obj, models.Model):  # TypeError: isinstance() arg 2 must be a type or tuple of types :- in this line error occurred if you not provide second argument correctly
    print("my_obj is a Model object")
else:
    print("my_obj is not a Model object")

In this example, we are using isinstance() to check if my_obj is an instance of the Model class. Since my_obj is a MyModel object, which is a subclass of Model, isinstance() returns True and the code prints “my_obj is a Model object”.

typeerror isinstance() arg 2 must be a type or tuple of types datetime

In the context of the datetime module, this error might occur if you are trying to use isinstance() to check the type of a datetime object, but you pass an invalid type as the second argument.

Here’s an example of how this error might occur in the context of the datetime module:

from datetime import datetime

now = datetime.now()

if isinstance(now, datetime):
    print("now is a datetime object")
else:
    print("now is not a datetime object")

In this example, we are using isinstance() to check if now is an instance of the datetime class. Since now is a datetime object, isinstance() returns True and the code prints “now is a datetime object”.

mock isinstance() arg 2 must be a type or tuple of types

In the context of the mock library, this error might occur if you are trying to use isinstance() to check the type of a mock object, but you pass an invalid type as the second argument. Here is a correct code to do this :-

from unittest.mock import Mock

my_mock = Mock()

if isinstance(my_mock, Mock):
    print("my_mock is a Mock object")
else:
    print("my_mock is not a Mock object")

typeerror: isinstance() arg 2 must be a type or tuple of types apache beam

Here’s an example of correct way to check instance in the context of Apache Beam :-

from apache_beam.transforms import PTransform

class MyTransform(PTransform):
    pass

my_transform = MyTransform()

if isinstance(my_transform, PTransform):
    print("my_transform is a PTransform object")
else:
    print("my_transform is not a PTransform object")

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