Fixing AttributeError: module ‘tarfile’ has no attribute ‘data_filter’ in Python

Introduction:

If you’re a Python developer, you might encounter unexpected errors when installing or working with Python packages. One such error is the AttributeError related to the ‘tarfile’ module, which can occur during the installation or usage of Python packages.

In this article, we’ll explore the cause of the AttributeError and how to fix it, along with a real-world example of encountering and resolving this issue.

Understanding the AttributeError:

The AttributeError with the ‘tarfile’ module typically arises when there’s an inconsistency or conflict with the Python installation or its dependencies. The error message might look like this:

AttributeError: module 'tarfile' has no attribute 'data_filter'

This error indicates that the ‘tarfile’ module doesn’t have the expected ‘data_filter’ attribute, which might be required by certain operations or packages.

Resolving the AttributeError:

To resolve the AttributeError with the ‘tarfile’ module, one common solution is to upgrade the ‘pip’ package manager to the latest version. This can be done using the following command:

python3 -m pip install --upgrade pip

Upgrading ‘pip’ ensures that you have the latest version, which may include bug fixes and improvements that address compatibility issues with Python modules and dependencies.

Real-world Example:

Let’s consider a real-world scenario where a Python developer encounters the AttributeError with the ‘tarfile’ module while installing or working with Python packages. They observe the error message and identify that upgrading ‘pip’ could potentially resolve the issue.

After running the command to upgrade ‘pip’, the developer re-attempts the installation or operation that previously resulted in the AttributeError. This time, the operation completes successfully without any errors, indicating that the issue has been resolved.

ImportError: No module named ‘boto3’

 

I got this error while I am trying to use boto3 module in python.

The main reason for this error is, there is no boto3 module installed.

To install boto3 user following command:

sudo pip3 install boto3

One thing you need to observe here is to use pip3 to install boto3.

If pip3 not installed in your node user following command to install it:

sudo apt-get install python3-pip

Python – check variable for None

 

To check if a variable is None use following code:

>>> val=None
>>> val is None
True

If you want to use above example with if condition use following code:

if not (val in None):
  print "val is not none"
else:
  print "val is none"

Python – ImportError: No module named memcache

While trying to connect memcached using python I got following error:

ImportError: No module named memcache

Since I imported memcache & it’s not available in my server I got the error message saying that “No module named memcache”.

To resolve this issue we need to install python-memcache module.

Use following command to install python-memcache:

$ pip install python-memcache

If  your OS is Ubuntu/Debian following command also works for you:

$ apt-get install python-memcache

After installing python-memcache we can seamlessly connect to memcached.

fatal error: Python.h: No such file or directory

While trying to install some python module I got following exception:

fatal error: Python.h: No such file or directory

Reason for exception:

If you haven’t properly installed the header files and static libraries for python dev this issue may occur.

To resolve this issue install python-dev module by using following command:

$ sudo apt-get install python-dev

Python – check if ip is public or private

 

netaddr is a Python library for representing and manipulating network addresses.

Installing netaddr library:

Use any of following command to install netaddr library

$ sudo pip install netaddr
or
$ easy_install netaddr

Observe following example for more details:

>>> from netaddr import *
>>> IPAddress('74.125.236.194').is_private()
False
>>> IPAddress('192.168.1.10').is_private()
True
>>> IPAddress('127.0.0.1').is_loopback()
True

IPAddress(‘input ip’).is_private() will return true if the input ip address private, else it will return false.

Reference: Netaddr

Python – find files in directory with extension

The glob module finds all the pathnames matching a specific pattern according to the rules used by the Unix Shell. No tilde expansion is done, but *, ?, and character ranges expressed with [] will be correctly matched.

Examples:

To list all files ending with *.txt in /home/guest directory:

>>> import glob
>>> glob.glob("/home/guest/*.txt")

Output:
[‘/home/guest/syslog.txt’, ‘/home/guest/mysql.txt’, ‘/home/guest/topics.txt’, ‘/home/guest/bus.txt’]

Similarly you can try others.

As mentioned above No tilde expansion will work, so following example will return empty list.

>>> glob.glob("~/guest/*.txt")

Output:
[]

Python – remove first and last character

 

By using slicing technique we can remove first ans last character from a string.

Observe following example for more details:

>>> input = "abcd"
>>> input[1:-1]

Output:
‘bc’

In above example I removed a and d from input string (‘abcd’) with input[1:-1], so out our output is ‘bc’.

Python – get system hostname

 

By using socket.gethostname() we can get hostname of system:

>>> import socket
>>> socket.gethostname()
'localhost'

There is one more way to get hostname is by using platform.node():

>>> import platform
>>> platform.node()
'localhost'

Python – count duplicates in list

 

By using python collections.Counter(<LIST>) we can count number of duplicates in list.

Observer following example for more details:

>>> import collections
>>> mylist = ['a', 'b', 'a', 'c', 'a', 'b']
>>> uniqCount = collections.Counter(mylist)
>>> uniqCount
Counter({'a': 3, 'b': 2, 'c': 1})
>>> uniqCount.keys()
['a', 'c', 'b']
>>> uniqCount.values()
[3, 1, 2]