diff --git a/.gitignore b/.gitignore
index 68ca39690..35db47f33 100644
--- a/.gitignore
+++ b/.gitignore
@@ -11,23 +11,3 @@ tex2pdf*
 .coverage
 .idea
 .vscode
-02_crowsnest/crowsnest.py
-03_picnic/picnic.py
-04_jump_the_five/jump.py
-05_howler/howler.py
-06_wc/wc.py
-07_gashlycrumb/gashlycrumb.py
-08_apples_and_bananas/apples.py
-09_abuse/abuse.py
-10_telephone/telephone.py
-11_bottles_of_beer/bottles.py
-12_ransom/ransom.py
-13_twelve_days/twelve_days.py
-14_rhymer/rhymer.py
-15_kentucky_friar/friar.py
-16_scrambler/scrambler.py
-17_mad_libs/mad.py
-18_gematria/gematria.py
-19_wod/wod.py
-20_password/password.py
-21_tictactoe/tictactoe.py
diff --git a/01_hello/Makefile b/01_hello/Makefile
index 1cbd24b42..37577a3d0 100644
--- a/01_hello/Makefile
+++ b/01_hello/Makefile
@@ -2,3 +2,6 @@
 
 test:
 	pytest -xv test.py
+
+lint:
+	pylint hello.py
diff --git a/01_hello/hello.py b/01_hello/hello.py
new file mode 100755
index 000000000..e52da0a24
--- /dev/null
+++ b/01_hello/hello.py
@@ -0,0 +1,32 @@
+#!/usr/bin/env python3
+"""
+Author: Johan Runesson <info@johanrunesson.se>
+Purpose: Say hello
+"""
+
+import argparse
+
+
+# --------------------------------------------------
+def get_args():
+    """Get the command-line arguments"""
+    parser = argparse.ArgumentParser(description='Say hello')
+    parser.add_argument('-n',
+                        '--name',
+                        metavar='name',
+                        default='World',
+                        help='Name to greet')
+    return parser.parse_args()
+
+
+# --------------------------------------------------
+def main():
+    """Start things up"""
+    args = get_args()
+
+    print('Hello, ' + args.name + '!')
+
+
+# --------------------------------------------------
+if __name__ == '__main__':
+    main()
diff --git a/02_crowsnest/crowsnest.py b/02_crowsnest/crowsnest.py
new file mode 100755
index 000000000..58e0dabd3
--- /dev/null
+++ b/02_crowsnest/crowsnest.py
@@ -0,0 +1,37 @@
+#!/usr/bin/env python3
+"""
+Author : Johan Runesson <info@johanrunesson.se>
+Date   : 2020-08-03
+Purpose: Crow\'s Nest -- choose the correct article 
+"""
+
+import argparse
+
+
+# --------------------------------------------------
+def get_args():
+    """Get command-line arguments"""
+
+    parser = argparse.ArgumentParser(
+        description='Crow\'s Nest -- choose the correct article',
+        formatter_class=argparse.ArgumentDefaultsHelpFormatter)
+
+    parser.add_argument('word', metavar='word', help='A word')
+
+    return parser.parse_args()
+
+
+# --------------------------------------------------
+def main():
+    """Start things up"""
+
+    args = get_args()
+    word = args.word
+    article = 'an' if word[0].lower() in 'aeiou' else 'a'
+
+    print(f'Ahoy, Captain, {article} {word} off the larboard bow!')
+
+
+# --------------------------------------------------
+if __name__ == '__main__':
+    main()
diff --git a/03_picnic/picnic.py b/03_picnic/picnic.py
new file mode 100755
index 000000000..9f8ac5ef9
--- /dev/null
+++ b/03_picnic/picnic.py
@@ -0,0 +1,58 @@
+#!/usr/bin/env python3
+"""
+Author : Johan Runesson <info@johanrunesson.se>
+Date   : 2020-08-03
+Purpose: Picnic game 
+"""
+
+import argparse
+
+
+# --------------------------------------------------
+def get_args():
+    """Get command-line arguments"""
+
+    parser = argparse.ArgumentParser(
+        description='Picnic game',
+        formatter_class=argparse.ArgumentDefaultsHelpFormatter)
+
+    parser.add_argument('item',
+                        metavar='item',
+                        nargs='+',
+                        help='Item(s) to bring')
+
+    parser.add_argument('-s',
+                        '--sorted',
+                        action='store_true',
+                        help='Sort the items')
+
+    return parser.parse_args()
+
+
+# --------------------------------------------------
+def main():
+    """Start things up"""
+
+    args = get_args()
+    items = args.item
+    sorted = args.sorted
+    num = len(items)
+
+    if sorted:
+        items.sort()
+
+    if num > 1:
+        items.insert(-1, 'and')
+
+    if num > 3:
+        last = items.pop();
+        items = ', '.join(items) + ' ' + last
+    else:
+        items = ' '.join(items)
+
+    print(f'You are bringing {items}.')
+
+
+# --------------------------------------------------
+if __name__ == '__main__':
+    main()
diff --git a/04_jump_the_five/jump.py b/04_jump_the_five/jump.py
new file mode 100755
index 000000000..9f41d9db6
--- /dev/null
+++ b/04_jump_the_five/jump.py
@@ -0,0 +1,53 @@
+#!/usr/bin/env python3
+"""
+Author : Johan Runesson <info@johanrunesson.se>
+Date   : 2020-08-03
+Purpose: Jump the Five
+"""
+
+import argparse
+
+
+# --------------------------------------------------
+def get_args():
+    """Get command-line arguments"""
+
+    parser = argparse.ArgumentParser(
+        description='Jump the Five',
+        formatter_class=argparse.ArgumentDefaultsHelpFormatter)
+
+    parser.add_argument('number', metavar='str', help='A number')
+
+    return parser.parse_args()
+
+
+# --------------------------------------------------
+def main():
+    """Start things up"""
+
+    args = get_args()
+    number = args.number
+
+    jumper = {
+        '1': '9',
+        '2': '8',
+        '3': '7',
+        '4': '6',
+        '5': '0',
+        '6': '4',
+        '7': '3',
+        '8': '2',
+        '9': '1',
+        '0': '5'
+    }
+
+    for char in number:
+        print(jumper.get(char, char), end='')
+    print() # To get rid of the %-character at the end (not sure why it gets printed)
+
+    # print(number.translate(number.maketrans(jumper)))
+
+
+# --------------------------------------------------
+if __name__ == '__main__':
+    main()
diff --git a/05_howler/README.md b/05_howler/README.md
index 36bb0a24d..e69de29bb 100644
--- a/05_howler/README.md
+++ b/05_howler/README.md
@@ -1,73 +0,0 @@
-# Howler
-
-https://www.youtube.com/playlist?list=PLhOuww6rJJNNzo5zqtx0388myQkUKyrQz
-
-Write a program that uppercases the given text:
-
-```
-$ ./howler.py 'The quick brown fox jumps over the lazy dog.'
-THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG.
-```
-
-If the text names a file, uppercase the contents of the file:
-
-```
-$ ./howler.py ../inputs/fox.txt
-THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG.
-```
-
-If given no arguments, print a brief usage:
-
-```
-$ ./howler.py
-usage: howler.py [-h] [-o str] str
-howler.py: error: the following arguments are required: str
-```
-
-If the `-o` or `--outfile` option is present, write the output to the given file and print nothing:
-
-```
-$ ./howler.py ../inputs/fox.txt -o out.txt
-```
-
-There should now be an `out.txt` file with the contents:
-
-```
-$ cat out.txt
-THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG.
-```
-
-Respond to `-h` or `--help` with a longer usage:
-
-```
-$ ./howler.py -h
-usage: howler.py [-h] [-o str] str
-
-Howler (upper-cases input)
-
-positional arguments:
-  str                   Input string or file
-
-optional arguments:
-  -h, --help            show this help message and exit
-  -o str, --outfile str
-                        Output filename (default: )
-```
-
-Run the test suite to ensure your program is working correctly:
-
-```
-$ make test
-pytest -xv test.py
-============================= test session starts ==============================
-...
-collected 5 items
-
-test.py::test_exists PASSED                                              [ 20%]
-test.py::test_usage PASSED                                               [ 40%]
-test.py::test_text_stdout PASSED                                         [ 60%]
-test.py::test_text_outfile PASSED                                        [ 80%]
-test.py::test_file PASSED                                                [100%]
-
-============================== 5 passed in 0.40s ===============================
-```
diff --git a/05_howler/hagrid.txt b/05_howler/hagrid.txt
new file mode 100644
index 000000000..e69de29bb
diff --git a/05_howler/howler.py b/05_howler/howler.py
new file mode 100755
index 000000000..b2924ecb7
--- /dev/null
+++ b/05_howler/howler.py
@@ -0,0 +1,60 @@
+#!/usr/bin/env python3
+"""
+Author : Johan Runesson <info@johanrunesson.se>
+Date   : 2020-08-04
+Purpose: Howler (upper-cases input) 
+"""
+
+import argparse
+import os
+
+
+# --------------------------------------------------
+def get_args():
+    """Get command-line arguments"""
+
+    parser = argparse.ArgumentParser(
+        description='Howler (upper-cases input)',
+        formatter_class=argparse.ArgumentDefaultsHelpFormatter)
+
+    parser.add_argument('text',
+                        metavar='text',
+                        type=str,
+                        help='Input string or file')
+
+    parser.add_argument('-o',
+                        '--outfile',
+                        help='Output filename',
+                        metavar='str',
+                        type=str,
+                        default='')
+
+    return parser.parse_args()
+
+
+# --------------------------------------------------
+def main():
+    """Start things up"""
+
+    args = get_args()
+    text = args.text
+    outfile = args.outfile
+    output = text.upper()
+
+    # validate arguments inside get_args (see solution1.py)
+    if os.path.isfile(text):
+        fh_in = open(text)
+        output = fh_in.read().upper()
+        fh_in.close()
+
+    if outfile:
+        fh_out = open(outfile, 'wt')
+        fh_out.write(output)
+        fh_out.close()
+    else:
+        print(output)
+
+
+# --------------------------------------------------
+if __name__ == '__main__':
+    main()
diff --git a/05_howler/test.txt b/05_howler/test.txt
new file mode 100644
index 000000000..05b387ba1
--- /dev/null
+++ b/05_howler/test.txt
@@ -0,0 +1 @@
+hej hej he
diff --git a/05_howler/test2.txt b/05_howler/test2.txt
new file mode 100644
index 000000000..71f115934
--- /dev/null
+++ b/05_howler/test2.txt
@@ -0,0 +1 @@
+HEJ HEJ HE
diff --git a/06_wc/wc.py b/06_wc/wc.py
new file mode 100755
index 000000000..c3b0f6a70
--- /dev/null
+++ b/06_wc/wc.py
@@ -0,0 +1,52 @@
+#!/usr/bin/env python3
+"""Emulate wc (word count)"""
+
+import argparse
+import sys
+
+
+# --------------------------------------------------
+def get_args():
+    """Get command-line arguments"""
+
+    parser = argparse.ArgumentParser(
+        description='Emulate wc (word count)',
+        formatter_class=argparse.ArgumentDefaultsHelpFormatter)
+
+    parser.add_argument('file',
+                        metavar='FILE',
+                        nargs='*',
+                        default=[sys.stdin],
+                        type=argparse.FileType('rt'),
+                        help='Input file(s)')
+
+    return parser.parse_args()
+
+
+# --------------------------------------------------
+def main():
+    """Start things up"""
+
+    args = get_args()
+
+    total_lines, total_bytes, total_words = 0, 0, 0
+    for fh in args.file:
+        num_lines, num_words, num_bytes = 0, 0, 0
+        for line in fh:
+            num_lines += 1
+            num_bytes += len(line)
+            num_words += len(line.split())
+
+        total_lines += num_lines
+        total_bytes += num_bytes
+        total_words += num_words
+
+        print(f'{num_lines:8}{num_words:8}{num_bytes:8} {fh.name}')
+
+    if len(args.file) > 1:
+        print(f'{total_lines:8}{total_words:8}{total_bytes:8} total')
+
+
+# --------------------------------------------------
+if __name__ == '__main__':
+    main()
diff --git a/07_gashlycrumb/gashlycrumb.py b/07_gashlycrumb/gashlycrumb.py
new file mode 100755
index 000000000..4646aaa51
--- /dev/null
+++ b/07_gashlycrumb/gashlycrumb.py
@@ -0,0 +1,51 @@
+#!/usr/bin/env python3
+"""
+Author : Johan Runesson <info@johanrunesson.se>
+Date   : 2020-08-04
+Purpose: Gashlycrumb
+"""
+
+import argparse
+
+
+# --------------------------------------------------
+def get_args():
+    """Get command-line arguments"""
+
+    parser = argparse.ArgumentParser(
+        description='Gashlycrumb',
+        formatter_class=argparse.ArgumentDefaultsHelpFormatter)
+
+    parser.add_argument('letter',
+                        metavar='letter',
+                        nargs='+',
+                        help='Letter(s)')
+
+    parser.add_argument('-f',
+                        '--file',
+                        help='Input file',
+                        metavar='FILE',
+                        type=argparse.FileType('rt'),
+                        default='gashlycrumb.txt')
+
+    return parser.parse_args()
+
+
+# --------------------------------------------------
+def main():
+    """Start things up"""
+
+    args = get_args()
+    dictionary = { line[0].lower(): line.rstrip() for line in args.file }
+    # dictionary = {}
+
+    # for line in args.file:
+    #     dictionary[line[0].lower()] = line.rstrip()
+
+    for letter in args.letter:
+        print(dictionary.get(letter.lower(), f'I do not know "{letter}".'))
+
+
+# --------------------------------------------------
+if __name__ == '__main__':
+    main()
diff --git a/08_apples_and_bananas/apples.py b/08_apples_and_bananas/apples.py
new file mode 100755
index 000000000..06cf9ac52
--- /dev/null
+++ b/08_apples_and_bananas/apples.py
@@ -0,0 +1,53 @@
+#!/usr/bin/env python3
+"""
+Author : Johan Runesson <info@johanrunesson.se>
+Date   : 2020-08-04
+Purpose: Apples and bananas
+"""
+
+import argparse
+import os
+
+
+# --------------------------------------------------
+def get_args():
+    """Get command-line arguments"""
+
+    parser = argparse.ArgumentParser(
+        description='Apples and bananas',
+        formatter_class=argparse.ArgumentDefaultsHelpFormatter)
+
+    parser.add_argument('text', metavar='text', help='Input text or file')
+
+    parser.add_argument('-v',
+                        '--vowel',
+                        help='The vowel to substitute',
+                        metavar='vowel',
+                        type=str,
+                        choices=list('aeiou'),
+                        default='a')
+
+    args = parser.parse_args()
+
+    if os.path.isfile(args.text):
+        args.text = open(args.text).read().rstrip()
+
+    return args
+
+
+# --------------------------------------------------
+def main():
+    """Start things up"""
+
+    args = get_args()
+    text = args.text
+    vowel = args.vowel
+
+    new_text = text.translate(str.maketrans('aeiouAEIOU', vowel * 5 + vowel.upper() * 5));
+
+    print(new_text)
+
+
+# --------------------------------------------------
+if __name__ == '__main__':
+    main()
diff --git a/09_abuse/abuse.py b/09_abuse/abuse.py
new file mode 100755
index 000000000..0796d3184
--- /dev/null
+++ b/09_abuse/abuse.py
@@ -0,0 +1,85 @@
+#!/usr/bin/env python3
+"""
+Author : Johan Runesson <info@johanrunesson.se>
+Date   : 2020-08-04
+Purpose: Heap abuse
+"""
+
+import argparse
+import random
+
+
+# --------------------------------------------------
+def get_args():
+    """Get command-line arguments"""
+
+    parser = argparse.ArgumentParser(
+        description='Heap abuse',
+        formatter_class=argparse.ArgumentDefaultsHelpFormatter)
+
+    parser.add_argument('-a',
+                        '--adjectives',
+                        help='Number of adjectives',
+                        metavar='adjectives',
+                        type=int,
+                        default=2)
+
+    parser.add_argument('-n',
+                        '--number',
+                        help='Number of insults',
+                        metavar='insults',
+                        type=int,
+                        default=3)
+
+    parser.add_argument('-s',
+                        '--seed',
+                        help='Random seed',
+                        metavar='seed',
+                        type=int,
+                        default=None)
+
+    args = parser.parse_args()
+
+    if args.adjectives < 1:
+        parser.error(f'--adjectives "{args.adjectives}" must be > 0')
+
+    if args.number < 1:
+        parser.error(f'--number "{args.number}" must be > 0')
+
+    return args
+
+
+# --------------------------------------------------
+def main():
+    """Start things up"""
+
+    args = get_args()
+    random.seed(args.seed)
+
+    adjectives = '''
+        bankrupt base caterwauling corrupt cullionly 
+        detestable dishonest false filthsome filthy 
+        foolish foul gross heedless indistinguishable 
+        infected insatiate irksome lascivious lecherous 
+        loathsome lubbery old peevish rascaly rotten 
+        ruinous scurilous scurvy slanderous sodden-witted 
+        thin-faced toad-spotted unmannered vile wall-eyed
+    '''.split()
+
+    nouns = '''
+        Judas Satan ape ass barbermonger beggar block boy 
+        braggart butt carbuncle coward coxcomb cur dandy 
+        degenerate fiend fishmonger fool gull harpy jack 
+        jolthead knave liar lunatic maw milksop minion 
+        ratcatcher recreant rogue scold slave swine traitor 
+        varlet villain worm
+    '''.split()
+
+    for _ in range(args.number):
+        adjective = ', '.join(random.sample(adjectives, k=args.adjectives))
+        print(f'You {adjective} {random.choice(nouns)}!')
+
+
+# --------------------------------------------------
+if __name__ == '__main__':
+    main()
diff --git a/10_telephone/telephone.py b/10_telephone/telephone.py
new file mode 100755
index 000000000..5f769df3f
--- /dev/null
+++ b/10_telephone/telephone.py
@@ -0,0 +1,73 @@
+#!/usr/bin/env python3
+"""
+Author : Johan Runesson <info@johanrunesson.se>
+Date   : 2020-08-07
+Purpose: Telephone
+"""
+
+import argparse
+import os
+import random
+import string
+
+
+# --------------------------------------------------
+def get_args():
+    """Get command-line arguments"""
+
+    parser = argparse.ArgumentParser(
+        description='Telephone',
+        formatter_class=argparse.ArgumentDefaultsHelpFormatter)
+
+    parser.add_argument('text', metavar='text', help='Input text or file')
+
+    parser.add_argument('-s',
+                        '--seed',
+                        help='Random seed',
+                        metavar='int',
+                        type=int,
+                        default=None)
+
+    parser.add_argument('-m',
+                        '--mutations',
+                        help='Percent mutations',
+                        metavar='int',
+                        type=float,
+                        default=0.1)
+
+    args = parser.parse_args()
+
+    if args.mutations < 0 or args.mutations > 1:
+        parser.error(f'--mutations "{args.mutations}" must be between 0 and 1')
+
+    if os.path.isfile(args.text):
+        args.text = open(args.text).read().rstrip()
+
+    return args
+
+
+# --------------------------------------------------
+def main():
+    """Start things up"""
+
+    args = get_args()
+    text = args.text
+    random.seed(args.seed)
+    alpha = ''.join(sorted(string.ascii_letters + string.punctuation))
+    num_mutations = round(len(text) * args.mutations)
+    indexes = random.sample(range(len(text)), num_mutations)
+
+    for i in indexes:
+        new_char = random.choice(alpha.replace(text[i], ''))
+        text = text[:i] + new_char + text[i+1:]
+        # alpha2 = alpha.replace(text[i], '')
+        # text = text[:i] + random.choice(alpha2) + text[i+1:]
+         
+
+    print(f'You said: "{args.text}"')
+    print(f'I heard : "{text}"')
+
+
+# --------------------------------------------------
+if __name__ == '__main__':
+    main()
diff --git a/NOTES.md b/NOTES.md
new file mode 100644
index 000000000..807a2b99f
--- /dev/null
+++ b/NOTES.md
@@ -0,0 +1,116 @@
+# Notes
+
+## Links
+
+- https://docs.python.org/3/
+
+## Tips
+
+- The nargs (number of arguments) option to argparse allows you to validate the number of arguments from the user. The asterisk ('*') means zero or more, whereas '+' means one or more.
+- If you define an argument using type=argparse.FileType('rt'), argparse will validate that the user has provided a readable text file and will make the value available in your code as an open file handle.
+- You can read and write from the standard in/out file handles by using sys.stdin and sys.stdout.
+
+## Tools
+
+Run tests:
+
+```
+pytest -xv test.py
+```
+
+Run lint:
+
+```
+pylint hello.py
+```
+
+## Tricks
+
+Make executable:
+
+```
+chmod +x hello.py
+```
+
+Add to PATH:
+
+```
+mkdir ~/bin
+cp 01_hello/hello.py ~/bin
+PATH=~/bin:$PATH
+```
+
+Get type of variable:
+
+```
+type(word)
+```
+
+Get character of string:
+
+```
+word = "hej"
+word[0] # h
+word[2] # j
+word[-1] # j
+word[:2] # he
+```
+
+Get length of string:
+
+```
+len('hej') # 3
+```
+
+Get help in repl:
+
+```bash
+python3
+help(str)
+```
+
+Read a file (reads the entire file into memory):
+
+```
+fh = open(text)
+text = fh.read()
+fh.close()
+```
+
+Read a file (without reading the entire file into memory):
+
+```
+fh = open(text)
+for line in fh:
+	print(line.upper())
+fh.close()
+```
+
+Handle text that might be a file of a string:
+
+```
+if os.path.isfile(args.text):
+	args.text = open(args.text)
+else:
+	args.text = io.StringIO(args.text + '\n')
+```
+
+Handle output to file if specified else to print:
+
+```
+out_fh = open(args.outfile, 'wt') if args.outfile else sys.stdout
+```
+
+Create a dictionary with a loop:
+
+```
+lookup = { line[0].upper(): line.rstrip() for line in fh }
+```
+
+Change characters in a string (non-deterministic) (good for speed and when working with large files:
+```
+new_text = ''
+for char in args.text:
+	new_text += random.choice(alpha) if random.random() <= args.mutations else char
+print(new_text)
+```
diff --git a/out.txt b/out.txt
new file mode 100644
index 000000000..1746bd0e2
--- /dev/null
+++ b/out.txt
@@ -0,0 +1,2 @@
+this is some text
+this is some more text