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The CORRECT OPTION is (d) error

Best explanation: seek() takes at least one ARGUMENT.

Right CHOICE is (c) os.remove(‘file’)

EXPLANATION: os.remove() is USED to delete FILES.

The correct ANSWER is (B) os.RENAME(existing_name, new_name)

Best explanation: os.rename() is used to rename FILES.

Right ANSWER is (B) fp.tell()

Easy explanation - It gives the current position as an OFFSET from the start of FILE.

Right CHOICE is (c) fp.close()

The EXPLANATION is: close() is a method of the FILE object.

Right choice is (a) fp.name

Easy EXPLANATION - name is an ATTRIBUTE of the FILE OBJECT.

The CORRECT option is (b) rw

Best explanation: Use r+, w+ or a+ to perform both read and WRITE operations USING a SINGLE FILE object.

The correct CHOICE is (a) wb+

For explanation: Here is the description below

“w”Opens a file for writing only. Overwrites the file if the file EXISTS. If the file does not exist, CREATES a new file for writing.

“wb” Opens a file for writing only in binary FORMAT. Overwrites the file if the file exists. If the file does not exist, creates a new file for writing.

“w+” Opens a file for both writing and reading. Overwrites the EXISTING file if the file exists. If the file does not exist, creates a new file for reading and writing.

“wb+” Opens a file for both writing and reading in binary format. Overwrites the existing file if the file exists. If the file does not exist, creates a new file for reading and writing.

The correct choice is (a) YES

Best explanation: Yes we can create a file in PYTHON. Creation of file is as shown below.

file = OPEN(“newfile.txt”, “w”)

file.write(“hello world in the NEW file\n”)

file.write(“and ANOTHER line\n”)

file.close().

The correct answer is (a) writeline()

To explain: With the writeline FUNCTION you can WRITE a list of strings to a file

fh = OPEN(“hello.txt”, “w”)

lines_of_text = [“a line of TEXT”, “another line of text”, “a third line”]

fh.writelines(lines_of_text).

Right CHOICE is (a) Close()

BEST explanation: f.close()to close it and free up any system resources TAKEN up by the open FILE.

Right option is (a) WRITE()

The explanation: To write a fixed sequence of CHARACTERS to a file

fh = open(“HELLO.txt”,”w”)

write(“Hello WORLD”).

The CORRECT choice is (b) Readlines()

To explain: The readline function reads a SINGLE LINE from the file FH = open(“filename”, “r”)

CONTENT = fh.readline().

Correct CHOICE is (a) READ()

The best I can explain: The read function READS all characters fh = OPEN(“FILENAME”, “r”)

content = fh.read().

Right choice is (c) Append

The EXPLANATION is: This opens the fhe FILE in appending MODE. That means, it will be OPEN for writing and EVERYTHING will be written to the end of the file.

fh =open(“filename_here”, “a”).

The CORRECT ANSWER is (a) read, append

The best I can EXPLAIN: R- reading,a-appending.

The correct answer is (a) fileObject.READLINES( sizehint );

The best I can explain: The METHOD readlines() reads until EOF using readline() and returns a list containing the lines. If the optional sizehint ARGUMENT is present, INSTEAD of reading up to EOF, whole lines totalling approximately sizehint bytes (possibly after rounding up to an internal buffer size) are read.

SYNTAX

Following is the syntax for readlines() method:

fileObject.readlines( sizehint );

Parameters

sizehint — This is the number of bytes to be read from the file.

Correct option is (b) file object = open(file_name [, access_mode][, buffering])

To explain I would say: Open() function correct syntax with the parameter details as shown below:

file object = open(file_name [, access_mode][, buffering])

Here is parameters’ detail:

file_name: The file_name argument is a string value that contains the NAME of the file that you want to access.

access_mode: The access_mode determines the mode in which the file has to be opened, i.e., READ, write, APPEND, etc. A complete list of possible values is given below in the table. This is optional parameter and the default file access mode is read (r).

buffering: If the buffering value is set to 0, no buffering will take place. If the buffering value is 1, line buffering will be performed while accessing a file. If you specify the buffering value as an integer greater than 1, then buffering ACTION will be performed with the indicated buffer size. If negative, the buffer size is the system default(default behavior).

Right ANSWER is (c) fileObject.WRITELINES(sequence)

The best I can EXPLAIN: The method writelines() writes a sequence of strings to the file. The sequence can be any iterable OBJECT producing strings, typically a list of strings. There is no return value.

SYNTAX

Following is the syntax for writelines() method:

fileObject.writelines( sequence ).

Correct choice is (b) It is USED for object deserialization

The best I can explain: We have been WORKING with simple textual data. What if we are working with objects rather than simple text? For such situations, we can use the pickle module. This module serializes Python objects. The Python objects are converted into byte streams and written to text files. This process is called PICKLING. The inverse OPERATION, reading from a file and reconstructing objects is called deserializing or UNPICKLING.

The CORRECT answer is (a) truncates the FILE SIZE

The best EXPLANATION: The method TRUNCATE() truncates the file size. Following is the syntax for truncate() method:

fileObject.truncate( [ size ])

Parameters

size — If this optional argument is present, the file is truncated to (at most) that size.

Correct choice is (a) sets the file’s current position at the OFFSET

Easiest explanation - Sets the file’s current position at the offset. The method SEEK() sets the file’s current position at the offset.

Following is the syntax for seek() method:

fileObject.seek(offset[, whence])

Parameters

offset — This is the position of the read/write pointer WITHIN the file.

whence — This is OPTIONAL and defaults to 0 which means absolute file positioning, other values are 1 which means seek relative to the current position and 2 means seek relative to the file’s end.

The correct CHOICE is (a) tells you the current position within the file

Easy EXPLANATION - The TELL() method tells you the current position within the file; in other WORDS, the next read or write will occur at that many bytes from the BEGINNING of the file.

Correct answer is (B) a list of lines

To EXPLAIN: EVERY LINE is stored in a list and returned.

The CORRECT OPTION is (d) infile.readlines()

To explain: Execute in the SHELL to verify.

The correct choice is (B) outfile = open(“c:\\scores.txt”, “W”)

The best I can explain: w is used to indicate that file is to be WRITTEN to.

The correct CHOICE is (d) >>> re.match(‘ab*’, ‘BA’)

Explanation: In the code shown above, ab* will match to ‘a’ or ‘ab’ or ‘a’ followed by any NUMBER of B’s. HENCE the only line of code from the above options which does not result in a match is:

>>> re.match(‘ab*’, ‘ba’).

The CORRECT option is (a) re.purge

Easy explanation - The function re.purge is USED to clear the cache and it does not accept any ARGUMENTS.

Right answer is (d) ‘pq+’ matches ‘p’

EXPLANATION: All of the above statements are correct except that ‘pq+’ match ‘p’. ‘pq+’ will match ‘p’ FOLLOWED by any non-zero number of Q’s, but it will not match ‘p’.

Correct answer is (b) re.compile.groupindex

Best explanation: The FUNCTION re.compile.groupindex RETURNS a dictionary MAPPING GROUP NAMES to group numbers.

Right option is (c) re.match(‘GEORGE(?=Washington)’, ‘GeorgeWashington’)

BEST explanation: The code SHOWN above demonstrates the use of the function re.match, alongwith the special character ?=. This results in a match only when ‘George’ is immediately followed by ‘Washington’. Also, we have not used the MODULE to IGNORE case. Hence the match is case-sensitive. Therefore the only option which results in a match is:

re.match(‘George(?=Washington)’, ‘GeorgeWashington’)

The CORRECT choice is (d) (?#…)

Easy EXPLANATION - The special character (?#…) represent a comment, that is, the contents of the PARENTHESIS are SIMPLY ignored.

The correct OPTION is (C) Matches a pattern from any part of a string

The BEST I can EXPLAIN: The re module of PYTHON consists of a function re.search. It’s function is to match a pattern from anywhere in a string.

The correct ANSWER is (c) re.I

Explanation: The function re.I (that is, re.IGNORECASE) RESULTS in case-insensitive matching. That is, EXPRESSIONS such as [A-Z] will match LOWERCASE characters too.

Right ANSWER is (C) re.purge()

The best I can explain: The function which clears the REGULAR EXPRESSION cache is re.purge(). NOTE that this function takes zero positional arguments.

The correct option is (a) >>> re.SEARCH(‘aaaa’, “alohaaaa”, 0)

Explanation: The output shown above is that of a search function, whose pattern is ‘aaaa’ and the STRING is that of 8 characters. The only option which matches all these criteria is:

 >>> re.search(‘aaaa’, “alohaaaa”, 0)

The correct choice is (b) EXACTLY 5

The explanation: The character {m} is USED to match exactly m CHARACTERS to the PREVIOUS regular expression. HENCE the expression a{5} will match exactly 5 characters and not less than that.