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- [Instructor] In this
self check exercise,

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we'd like you to use the CSV module

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that you just saw in the preceding video

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to create the grades.csv file

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and to write into that file
the comma-separated values

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that you see here in
the problem statement.

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Then we'd like you to
read that file back in

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and display it formatted in three columns

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with the column names ID, Name, and Grade.

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So go ahead and pause the
video and give that a shot,

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then come back to see the answer.

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Okay, let's go ahead and do this.

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We'll first import the CSV
module so that we can use it

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to write records into a
comma-separated value file.

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Next, we'll open grades.csv for writing.

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Again, there is that newline
equals empty string argument.

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And we're going to treat this file

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as the variable name grades,
which we will then use

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to create a comma-separated
value file writer.

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That writer object is then used

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to invoke the writerow
method once for each

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of the three records of
information that we are outputting.

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Notice again this is a list being passed

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into the writerow function.

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So let's go ahead and execute that.

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And now to read that data back in,

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we have a separate with statement.

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We're reading from the grades.csv
file, open for reading.

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Again, newline equals
empty string to ensure

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that the newline characters
are handled correctly.

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We print out our formatted column heads

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and create a reader to
read from the file grades

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and we then use a for loop
to read one record at a time

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from that comma-separated value file.

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Each of the records has
three pieces of information,

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so we split those off from the record

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that we're currently processing

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and then we format those
as three columns of output.

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So let's execute that, and you
can see indeed the three rows

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of data with the column
heads as specified back here

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in the problem statement.