Problem Solving And Python Programming Set 16

Answer: all of the mentioned

Explaination:
the program will throw an error.

Answer: infile.read(2)

Explaination:
execute in the shell to verify.

Answer: infile.readlines()

Explaination:
execute in the shell to verify.

Answer: true

Explaination:
the with statement when used with open file guarantees that the file object is closed when the with block exits.

Answer: raw_input & input

Explaination:
python provides two built-in functions to read a line of text from standard input, which by default comes from the keyboard. these functions are:

Answer: rename

Explaination:
rename is not the attribute of file rest all are files attributes.

Answer: tells you the current position within the file

Explaination:
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.

Answer: rename(current_file_name, new_file_name)

Explaination:
this is the correct syntax which has shown below.

Answer: remove(file_name)

Explaination:
remove(file_name)

Answer: displays output

Explaination:
it displays the output as shown below. the method next() is used when a file is used as an iterator, typically in a loop, the next() method is called repeatedly. this method returns the next input line, or raises stopiteration when eof is hit.

Answer: sets the file’s current position at the offset

Explaination:
sets the file’s current position at the offset. the method seek() sets the file’s current position at the offset.

Answer: truncates the file size

Explaination:
the method truncate() truncates the file size. following is the syntax for truncate() method:

Answer: all of the mentioned

Explaination:
standard input, standard output and standard error. standard input is the data that goes to the program. the standard input comes from a keyboard. standard output is where we print our data with the print keyword. unless redirected, it is the terminal console. the standard error is a stream where programs write their error messages. it is usually the text terminal.

Answer: sanfoundry

Explaination:
in order to work with standard i/o streams, we must import the sys module. the read() method reads one character from the standard input. in our example we get a prompt saying “enter your name”. we enter our name and press enter. the enter key generates the new line character: \n.

Answer: hello python

Explaination:
none output:

Answer: b

Explaination:
mode meaning is as explained below:

Answer: it is used for object serialization

Explaination:
pickle is the standard mechanism for object serialization. pickle uses a simple stack-based virtual machine that records the instructions used to reconstruct the object. this makes pickle vulnerable to security risks by malformed or maliciously constructed data, that may cause the deserializer to import arbitrary modules and instantiate any object.

Answer: it is used for object deserialization

Explaination:
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.

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

Explaination:
open() function correct syntax with the parameter details as shown below: file object = open(file_name [, access_mode] [, buffering])

Answer: flushes the file when closing them

Explaination:
the method flush() flushes the internal buffer. python automatically flushes the files when closing them. but you may want to flush the data before closing any file.

Answer: fileobject.writelines(sequence)

Explaination:
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.

Answer: fileobject.readlines( sizehint );

Explaination:
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.

Answer: read, append

Explaination:
r- reading, a-appending.

Answer: write

Explaination:
this opens the file for writing. it will create the file if it doesn’t exist, and if it does, it will overwrite it.

Answer: append

Explaination:
this opens the fhe file in appending mode. that means, it will be open for writing and everything will be written to