Python is now one of the most popular and skillful languages in programming domain. In this article, I will take you through some of the most important Python interview questions you need to know. To sit in an interview you must be familiar with most of the basics of Python.
If you have covered the basics with some python projects along then it’s the python interview question that you must be searching for. But before I dive into the python interview questions if you have still not worked on any Python project then I suggest you start with it soon as it will help you to make an impact in your interview.
Also, Read – Maths for Machine Learning.
You can get some python projects here. Now let’s have a look at some common python interview questions.
Common Python Interview Questions:
Why wouldn’t you want to use Python in an app?
The main drawback of Python is performance – it won’t run as quickly as fully compiled languages such as C and C ++. On the other hand, it’s pretty fast for most applications, and typical Python code runs near C speed anyway because it calls linked C code in the interpreter.
How are CPython, Jython, and IronPython different?
CPython is the standard implementation of the language. Jython and IronPython implement Python programs for use in Java and .NET environments, respectively; they are alternative compilers for Python.
What is a namespace and how does it relate to module files?
A namespace is just a package of variables. It takes the form of an object with attributes in Python. Each module file is automatically a namespace, that is, a set of variables reflecting the assignments made at the top level of the file. Namespaces help avoid name collisions in Python programs: because each module file is a stand-alone namespace, files must explicitly import other files to use their names.
What does “mapping” mean and what kind of kernel is a mapping?
The term “mapping” refers to an object that maps keys to associated values. The Python dictionary is the only type of mapping in the base type set. Mappings do not maintain any left-to-right position order; they support access to stored data by key, as well as type-specific method calls.
How can you convert octal, hexadecimal or binary string to an integer?
The int (S, base) function can be used to convert octal and hexadecimal strings to normal integers (pass 8, 16, or 2 for the base). The eval (S) function can also be used for this purpose, but it is more expensive to run and can have security concerns.
Why can you use the string module instead of string method calls?
You should never use the string module instead of string object method calls today, it is deprecated and its calls are completely removed in Python 3.X. The only valid reason for using the string module today is for its other tools, such as the built-in constants. You can also see it appear in what is now very old and dusty Python code.
Why might you use a dictionary instead of a list?
Dictionaries are generally best when the data is labelled (a record with field names, for example); lists are best suited for collections of unlabeled items (such as all files in a directory). Searching a dictionary is also generally faster than searching a list, although this may vary by program.
When does Python consider an object true?
An object is considered true if it is a non-zero number or a non-empty collection object. The built-in words True and False are essentially predefined to have the same meaning as the integers 1 and 0, respectively.
What is the most common coding mistake among Python beginners?
Forgetting to type the colon at the end of the header line in a compound is the most common mistake for beginners.
How might you use the print operation to send a text to an external file?
To print to a file for a single print operation, you can use the call form print (X, file = F) of 3.X, use the extended print file >> of 2.X, the form X declaration or manually assign sys.stdout to an open file before printing and restore the original after. You can also redirect all printed text from a program to a file with special syntax in the system shell, but this is outside the scope of Python.
How might you code a multiway branch in Python?
An if statement with multiple elif clauses is often the easiest way to code a multipath branch, but not necessarily the most concise or flexible. Indexing the dictionary can often achieve the same result, especially if the dictionary contains callable functions encoded with def statements or lambda expressions.
How can you code a counter-based loop in Python?
Counter loops can be encoded with a while statement that tracks the index manually, or with a for loop that uses the built-in range function to generate successive integer offsets. The preferred way to work in Python also isn’t if you just have to iterate through all the elements in a sequence. Instead, use a simple for loop, with no ranges or counters, if possible; it will be easier to code and generally faster to execute.
How can you obtain a list of the available attributes in an object?
The built-in dir(X) function returns a list of all the attributes attached to any object. A list comprehension of the form [a for a in dir(X) if not a.starts with(‘__’)] can be used to filter out internals names with underscores.
What does a function return if it has no return statement in it?
A function returns the None object by default if the control flow falls off the end of the function body without running into a return statement. Such functions are usually called with expression statements, as assigning their None results to variables is generally pointless. A return statement with no expression in it also returns None.
These were some of the most common Python interview questions. I hope you liked this article on some common Python Interview questions. Feel free to ask your valuable questions in the comments section below.
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