This shows you how to compress and decompress a typical text file using Python module gzip ...

# using module gzip to compress and decompress files
# default compression level is 9 (out of 1-9)
# needs Python27 or higher
# tested with Python27 and Python32  by vegaseat

import gzip

txt_file = "Edictionary.txt"
gz_file = "Edictionary.gz"

# reads in a 747kb .txt file, compresses to a 201kb .gz file
# mode='rb' is needed for the text file
with open(txt_file, 'rb') as f_in:
    with gzip.open(gz_file, 'wb') as f_out:
        f_out.writelines(f_in)

print("Read .gz file in as one string ..")
with gzip.open(gz_file, 'rb') as f:
    # decode <class 'bytes'> to string
    # .decode("utf8") does not work here
    text2 = f.read().decode("latin1")

print("Show first 80 characters:")
print(text2[:80])

print('-'*37)

# a mildly different approach using the class
print("Read .gz file in as list of lines ...")
gzin = gzip.GzipFile(gz_file, 'rb')
lines = gzin.readlines()
gzin.close()

print("Show first 10 lines:")
for line in lines[:10]:
    # decode <class 'bytes'> to string
    line = line.decode("latin1").rstrip()
    print(line)

'''result ...
Read .gz file in as one string ..
Show first 80 characters:
Aachen
aardvark
aardvarks
aaron
abaci
aback
abacus
abacuses
abaft
abalo
-------------------------------------
Read .gz file in as list of lines ...
Show first 10 lines:
Aachen
aardvark
aardvarks
aaron
abaci
aback
abacus
abacuses
abaft
abalone
'''

Python comes with module sqlite3 to create and process databases that can be queried with its common query language. First, let's create a database file ...

# explore Python module sqlite3
# create a database file
# the query language is in optional upper case
# using unique id numbers prevents appending an existing db file 
# tested with Python27 and Python32

import sqlite3

# create/connect to a permanent database file
file_name = "stock_portfolio2.db3"
con = sqlite3.connect(file_name)

# establish the cursor
cur = con.cursor()

# if it doesn't exist yet, create the table named stocks
# give each transaction a unique id number
cur.execute('''CREATE TABLE IF NOT EXISTS stocks
    (id INT PRIMARY KEY, date TEXT, trans TEXT, 
    symbol TEXT, qty REAL, price REAL)''')

# insert several lines at once using a
# list of (id, date, trans, symbol, qty, price) tuples
# each tranaction is given a unique id for data security
# the unique id primary key prevents any existing database file
# from being appended with a potentially conflicting data id 
try:
    stocks = [
    (100, '2011-05-07', 'buy', 'AZN', 500, 55.05),
    (101, '2011-05-07', 'buy', 'CAT', 200, 110.34),
    (102, '2011-05-07', 'sell', 'IBM', 100, 168.89),
    (103, '2011-05-07', 'buy', 'GE', 2000, 20.01)
    ]
    # the ? placeholders match tuple items
    cur.executemany("""INSERT INTO stocks
    VALUES (?, ?, ?, ?, ?, ?)""", stocks)
except:
    pass

# commit current data to the db file
con.commit()

# quickly test the database, in sorted order by symbol
cur.execute('SELECT * FROM stocks ORDER BY symbol')
# fetch all data rows
for row in cur.fetchall():
    print(row)

'''
(100, u'2011-05-07', u'buy', u'AZN', 500.0, 55.05)
(101, u'2011-05-07', u'buy', u'CAT', 200.0, 110.34)
(103, u'2011-05-07', u'buy', u'GE', 2000.0, 20.01)
(102, u'2011-05-07', u'sell', u'IBM', 100.0, 168.89)
'''

# done
con.close()

Now let's use the database file we just created ...

# explore Python module sqlite3
# read an existing database file
# query language in upper case (optional)
# tested with Python27 and Python32

import sqlite3

# connect to the permanent database file
file_name = "stock_portfolio2.db3"
con = sqlite3.connect(file_name)

# establish the cursor
cur = con.cursor()

# use cursor method execute() to test the database
cur.execute('SELECT * FROM stocks')
col_name_list = [tup[0] for tup in cur.description]
print("Table header:")
print(col_name_list)

'''
Table header:
['id', 'date', 'trans', 'symbol', 'qty', 'price']
'''

print('-'*50)

cur.execute('SELECT * FROM stocks')
# fetch first data row
row = cur.fetchone()
print(row)

'''result Python32 ...
(100, '2011-05-07', 'buy', 'AZN', 500.0, 55.05)
'''

print('-'*50)

cur.execute('SELECT id FROM stocks')
# fetch id numbers of all data rows
for row in cur.fetchall():
    print(row)

'''
(100,)
(101,)
(102,)
(103,)
'''

print('-'*50)

cur.execute('SELECT trans, qty, symbol, date FROM stocks')
# fetch selected items of all data rows
for row in cur.fetchall():
    print("%s %s %s on %s" % row)

'''
buy 500.0 AZN on 2011-05-07
buy 200.0 CAT on 2011-05-07
sell 100.0 IBM on 2011-05-07
buy 2000.0 GE on 2011-05-07
'''

# done
con.close()

I hope you can dream up a better example of a database.

Here we use the module matplotlib to plot a histogram (bar chart) of characters 'a' through 'z' as they appear in a given text ...

# create a list of [char,freq] lists of a text
# the plotting part needs the matplotlib module
# from
# http://sourceforge.net/projects/matplotlib/files/matplotlib/
# Windows installer matplotlib-1.0.1.win32-py2.7.exe
# or for Python32 use
# Windows installer matplotlib-1.1.0.dev.win32-py3.2.exe
# from
# http://www.lfd.uci.edu/~gohlke/pythonlibs/
# tested with Python27 and Python32  by  vegaseat

# use pylab namespace for clarity
import matplotlib.pylab as pylab

# just a simple text for testing
text = """\
Mississippi
"""

alpha = 'abcdefghijklmnopqrstuvwxyz'
# create initial list of [char,freq] lists
# of all lower case characters and freq=0
alpha_freq = [[c, 0]  for c in alpha]

print(alpha_freq)  # test
print('-'*60)

# increment the freq of a given character
for c in text.lower():
    if c in alpha:
        ix = alpha.index(c)
        alpha_freq[ix][1] += 1
        
print(alpha_freq)  # test
print('-'*60)

# use alpha_freq list to plot a char, freq histogram 
# using the matplotlib module's pylab
fig = pylab.figure()
ax = fig.add_subplot(111)
# data points ...
heights = [freq for c, freq in alpha_freq]
values = range(len(alpha))
# draw a matlib bar chart
pylab.bar (values, heights)
pylab.grid (True)
pylab.title ('Letter frequency in a text')
pylab.xlabel ('char a-z')
ax.set_xticks(values)
ax.set_xticklabels(tuple(alpha))
pylab.ylabel ('counts')

pylab.show()

A simpler matplotlib example ...

# plotting with the pylab module from matplotlib
# http://sourceforge.net/projects/matplotlib/files/matplotlib/
# used Windows installer matplotlib-1.0.1.win32-py2.7.exe
# modified Ene's code, tested with Python27

import math
import matplotlib.pylab as pylab

# create the x list data
# arange() is just like range() but allows float numbers
# actually uses numpy's arange()
#
x_list = pylab.arange(0.0, 5.0, 0.01)

# calculate the y list data
#
y_list = []
for x in x_list:
    # give it some fancy decaying function
    y = math.cos(2*math.pi*x) * math.exp(-x)
    y_list.append(y)

pylab.xlabel("x")
pylab.ylabel("cos(2pi * x) * exp(-x)")

# draw the plot with a blue line 'b' (default)
# using x,y data from the x_list and y_list
#
# other drawing styles -->
# 'r' red line, 'g' green line, 'y' yellow line
# 'ro' red dots, 'r.' smaller red dots, 'r+' red pluses
# 'r--' red dashed line, 'g^' green triangles, 'bs' blue squares
# 'rp' red pentagons, 'r1', 'r2', 'r3', 'r4' just check them out
#
pylab.plot(x_list, y_list, 'b')

# optionally save the plot as a .png image file
pylab.savefig('pylab_fancy.png')

# show the pylab plotting window
# zoom the graph, drag the graph, change the margins, save the graph
pylab.show()

Something simple, but handy at times ...

# convert an integer number to its binary representation
# and pad the result with a specified number of leading zeros
# tested with Python27 and Python32  by  vegaseat

def int2binpad(num, bits=4):
    """
    returns the binary of integer num, using bits
    number of digits, will pad with leading zeros
    """
    bs = ''
    for x in range(0, bits):
        if 2**x == 2**x & num:
            bs = '1' + bs
        else:
            bs = '0' + bs
    return bs

# testing ...
if __name__ == '__main__':
    print(int2binpad(255, 12))  # 000011111111
    print(int2binpad(254, 12))  # 000011111110
    print(int2binpad(76, 8))    # 01001100
    print(int2binpad(3))        # 0011

Something simple, but handy at times ...

# convert an integer number to its binary representation
# and pad the result with a specified number of leading zeros
# tested with Python27 and Python32  by  vegaseat

def int2binpad(num, bits=4):
    """
    returns the binary of integer num, using bits
    number of digits, will pad with leading zeros
    """
    bs = ''
    for x in range(0, bits):
        if 2**x == 2**x & num:
            bs = '1' + bs
        else:
            bs = '0' + bs
    return bs

# testing ...
if __name__ == '__main__':
    print(int2binpad(255, 12))  # 000011111111
    print(int2binpad(254, 12))  # 000011111110
    print(int2binpad(76, 8))    # 01001100
    print(int2binpad(3))        # 0011

Darn. getting those post duplicates again!

If you wan to get numeric input, optionally within a range of values, you can use the Tkinter GUI toolkit (comes with your Python installation) and its small pop-up dialogs in a console program ...

# use Tkinter's simple dialogs (pop-up) to ask for input
# minvalue and maxvalue are optional

try:
    # for Python2
    import Tkinter as tk
    import tkSimpleDialog as tksd
except ImportError:
    # for Python3
    import tkinter as tk
    import tkinter.simpledialog as tksd

root = tk.Tk()
# show input dialogs without the Tkinter window
root.withdraw()

# if a non-numeric value is entered, will prompt again
price = tksd.askfloat("Price", "Enter the price of the item:")
print(price)
# use askfloat or askinteger (whole items only)
quantity = tksd.askinteger("Quantity", "Number of items needed:",
    minvalue=1, maxvalue=1000)
print(quantity)

result = "Total cost is %0.2f" % (price*quantity)
print(result)

# you could even use askstring() to display the result
sf = "%0.2f" % (price*quantity)
tksd.askstring("Result", "Total cost is:", initialvalue=sf)