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Write scripts for the following questions, and upload them to the course website. You do not need to upload output files.

Begin each script with a comment that includes your name, the date, and the question number.

Here are some data files that can be downloaded and used for testing purposes. Download these files and save them in your working directory.

Name this script "q:lines".
[5 pts] Write a Python3 script that opens and reads a disk file. Your script must prompt for and receive a file name. It must then open and read each line of the file.

[10 pts] Your script must calculate and report the number of lines in the file, and the average length of the lines. Report the average length to two decimal places.

[5 pts] Also open a disk file for writing, named "output.txt". Write the file name and the report to it.

Here are example outputs for some of the data files listed above:
```
$ python3 ./q:lines.py
What file? limerick-05.txt
5 lines
average line length = 28.40
$
$ python3 ./q:lines.py
What file? sp0.txt
48 lines
average line length = 64.77
$
$ python3 ./q:lines.py
What file? naval-ship-names.txt
128 lines
average line length = 65.52
$
$ python3 ./q:lines.py
What file? happy.txt
52 lines
average line length = 33.17
$
$ python3 q:lines.py
What file? earth-quarter.txt
2826 lines
average line length = 46.90
$
```
Name this script "q:words".
[10 pts] Write a Python3 script that expects to be run from the command line, with one argument. The argument is a filename. You must open and read the contents of the file. (Hint: It's simpler to read the entire file at once, instead of line-by-line.)

[10 pts] Your script must report the longest word and its length; the average word length; and the shortest word and its length. (If there is more than one word of a given length, any of them is good enough.)

[5 pts] Use at least one list comprehension to do the calculations.
Here are example outputs for some of the data files listed above:
```
$ python3 q:words.py
Usage: q:words.py <datafile>
$
$ python3 q:words.py limerick-05.txt
  25 words
   10 up-to-date
 4.68 average length
    2 to
$
$ python3 q:words.py happy.txt
 278 words
   14 refrigeration.
 5.00 average length
    1 a
$
$ python3 q:words.py sp0.txt
 538 words
   14 north-easterly
 4.64 average length
    1 a
$
$ python3 q:words.py naval-ship-names.txt
1430 words
   15 perpendiculars,
 4.86 average length
    1 t
$
$ python3 q:words.py earth-quarter
23091 words
   39 http://www.gutenberg.org/5/8/9/1/58912/
 4.68 average length
    1 a
$
```
Name this script "q:worddistrib".
[5 pts] Write a Python3 script that expects to be run from the command line, with one argument. The argument is a filename. You must open and read the contents of the file.

[5 pts] Your script must build a dictionary of distinct words (as keys) and the number of times each occurs.
[5 pts] For each word/key, build a list of the positions (indexes) that the word appears within the file.

[5 pts] Words should be converted to lowercase (or uppercase, your choice) — this is needed so that "the", "The", and "THE" are seen as the same word, rather than three different words.

[10 pts] Report the number of distinct words, the average number of occurrences of each word, and the word that appears most frequently along with how many times it appears. If more than one word occurs that many times, report all of them.
Here are example outputs for some of the data files listed above:
```
$ python3 q:worddistrib.py
Usage: q:worddistrib.py <datafile&gs;
$
$ python3 q:worddistrib.py limerick-05.txt
most frequent: 2
    he
    his
    of
    the
    to
    wizard
$
$ python3 q:worddistrib.py happy.txt
most frequent: 18
    fun
    happy
$
$ python3 q:worddistrib.py p0.txt
most frequent: 62
    spam,
$
$ python3 q:worddistrib.py naval-ship-names.txt
most frequent: 87
    the
$
$ python3 q:worddistrib.py earth-quarter.txt
most frequent: 1331
    the
$
```
Name this script "q:url".
[10 pts] Write a Python3 script that retrieves and reads a URL (webpage). The URL must be obtained from the command line; also obtain an output-filename from the command line. Example URLs are:
- "http://bloomu.edu/computer-science/"
- "http://whitehouse.gov".
[10 pts] Write the contents of the URL to a text file. The output filename comes from the command line, as in the examples below.

[5 pts] For each file, count the number of occurrences of the character "<" and of the character ">", and display the counts.
An example run might look like this (counts and file sizes may vary over time):
```
$ python3 q:url.py
Usage: q:url.py <URL> <output-filename>
$
$ python3 ./q:url.py  https://montcs.bloomu.edu montcs.html
  265 occurrences of <
  265 occurrences of >
$
$ python3 ./q:url.py  http://whitehouse.gov  wh.html
 1259 occurrences of <
 1253 occurrences of >
$ ls -l *.html
-rw-r--r-- 1 bobmon bobmon   6726 Mar 15 09:12 montcs.html
-rw-r--r-- 1 bobmon bobmon 116665 Mar 15 09:12 wh.html
$
```