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+---
+language: Python 2 (legacy)
+contributors:
+    - ["Louie Dinh", "http://ldinh.ca"]
+    - ["Amin Bandali", "https://aminb.org"]
+    - ["Andre Polykanine", "https://github.com/Oire"]
+    - ["evuez", "http://github.com/evuez"]
+    - ["asyne", "https://github.com/justblah"]
+    - ["habi", "http://github.com/habi"]
+    - ["Rommel Martinez", "https://ebzzry.io"]
+filename: learnpythonlegacy.py
+---
+
+Python was created by Guido Van Rossum in the early 90s. It is now one of the
+most popular languages in existence. I fell in love with Python for its
+syntactic clarity. It's basically executable pseudocode.
+
+Feedback would be highly appreciated! You can reach me at [@louiedinh](http://twitter.com/louiedinh)
+or louiedinh [at] [google's email service]
+
+Note: This article applies to Python 2.7 specifically, but should be applicable
+to Python 2.x. Python 2.7 is reaching end of life and will stop being
+maintained in 2020, it is though recommended to start learning Python with
+Python 3. For Python 3.x, take a look at the [Python 3 tutorial](http://learnxinyminutes.com/docs/python/).
+
+It is also possible to write Python code which is compatible with Python 2.7
+and 3.x at the same time, using Python [`__future__` imports](https://docs.python.org/2/library/__future__.html). `__future__` imports
+allow you to write Python 3 code that will run on Python 2, so check out the
+Python 3 tutorial.
+
+```python
+
+# Single line comments start with a number symbol.
+
+""" Multiline strings can be written
+    using three "s, and are often used
+    as comments
+"""
+
+####################################################
+# 1. Primitive Datatypes and Operators
+####################################################
+
+# You have numbers
+3  # => 3
+
+# Math is what you would expect
+1 + 1  # => 2
+8 - 1  # => 7
+10 * 2  # => 20
+35 / 5  # => 7
+
+# Division is a bit tricky. It is integer division and floors the results
+# automatically.
+5 / 2  # => 2
+
+# To fix division we need to learn about floats.
+2.0  # This is a float
+11.0 / 4.0  # => 2.75 ahhh...much better
+
+# Result of integer division truncated down both for positive and negative.
+5 // 3  # => 1
+5.0 // 3.0  # => 1.0 # works on floats too
+-5 // 3  # => -2
+-5.0 // 3.0  # => -2.0
+
+# Note that we can also import division module(Section 6 Modules)
+# to carry out normal division with just one '/'.
+from __future__ import division
+
+11 / 4  # => 2.75  ...normal division
+11 // 4  # => 2 ...floored division
+
+# Modulo operation
+7 % 3  # => 1
+
+# Exponentiation (x to the yth power)
+2 ** 4  # => 16
+
+# Enforce precedence with parentheses
+(1 + 3) * 2  # => 8
+
+# Boolean Operators
+# Note "and" and "or" are case-sensitive
+True and False  # => False
+False or True  # => True
+
+# Note using Bool operators with ints
+0 and 2  # => 0
+-5 or 0  # => -5
+0 == False  # => True
+2 == True  # => False
+1 == True  # => True
+
+# negate with not
+not True  # => False
+not False  # => True
+
+# Equality is ==
+1 == 1  # => True
+2 == 1  # => False
+
+# Inequality is !=
+1 != 1  # => False
+2 != 1  # => True
+
+# More comparisons
+1 < 10  # => True
+1 > 10  # => False
+2 <= 2  # => True
+2 >= 2  # => True
+
+# Comparisons can be chained!
+1 < 2 < 3  # => True
+2 < 3 < 2  # => False
+
+# Strings are created with " or '
+"This is a string."
+'This is also a string.'
+
+# Strings can be added too!
+"Hello " + "world!"  # => "Hello world!"
+# Strings can be added without using '+'
+"Hello " "world!"  # => "Hello world!"
+
+# ... or multiplied
+"Hello" * 3  # => "HelloHelloHello"
+
+# A string can be treated like a list of characters
+"This is a string"[0]  # => 'T'
+
+# You can find the length of a string
+len("This is a string")  # => 16
+
+# String formatting with %
+# Even though the % string operator will be deprecated on Python 3.1 and removed
+# later at some time, it may still be good to know how it works.
+x = 'apple'
+y = 'lemon'
+z = "The items in the basket are %s and %s" % (x, y)
+
+# A newer way to format strings is the format method.
+# This method is the preferred way
+"{} is a {}".format("This", "placeholder")
+"{0} can be {1}".format("strings", "formatted")
+# You can use keywords if you don't want to count.
+"{name} wants to eat {food}".format(name="Bob", food="lasagna")
+
+# None is an object
+None  # => None
+
+# Don't use the equality "==" symbol to compare objects to None
+# Use "is" instead
+"etc" is None  # => False
+None is None  # => True
+
+# The 'is' operator tests for object identity. This isn't
+# very useful when dealing with primitive values, but is
+# very useful when dealing with objects.
+
+# Any object can be used in a Boolean context.
+# The following values are considered falsey:
+#    - None
+#    - zero of any numeric type (e.g., 0, 0L, 0.0, 0j)
+#    - empty sequences (e.g., '', (), [])
+#    - empty containers (e.g., {}, set())
+#    - instances of user-defined classes meeting certain conditions
+#      see: https://docs.python.org/2/reference/datamodel.html#object.__nonzero__
+#
+# All other values are truthy (using the bool() function on them returns True).
+bool(0)  # => False
+bool("")  # => False
+
+
+####################################################
+# 2. Variables and Collections
+####################################################
+
+# Python has a print statement
+print "I'm Python. Nice to meet you!"  # => I'm Python. Nice to meet you!
+
+# Simple way to get input data from console
+input_string_var = raw_input(
+    "Enter some data: ")  # Returns the data as a string
+input_var = input("Enter some data: ")  # Evaluates the data as python code
+# Warning: Caution is recommended for input() method usage
+# Note: In python 3, input() is deprecated and raw_input() is renamed to input()
+
+# No need to declare variables before assigning to them.
+some_var = 5  # Convention is to use lower_case_with_underscores
+some_var  # => 5
+
+# Accessing a previously unassigned variable is an exception.
+# See Control Flow to learn more about exception handling.
+some_other_var  # Raises a name error
+
+# if can be used as an expression
+# Equivalent of C's '?:' ternary operator
+"yahoo!" if 3 > 2 else 2  # => "yahoo!"
+
+# Lists store sequences
+li = []
+# You can start with a prefilled list
+other_li = [4, 5, 6]
+
+# Add stuff to the end of a list with append
+li.append(1)  # li is now [1]
+li.append(2)  # li is now [1, 2]
+li.append(4)  # li is now [1, 2, 4]
+li.append(3)  # li is now [1, 2, 4, 3]
+# Remove from the end with pop
+li.pop()  # => 3 and li is now [1, 2, 4]
+# Let's put it back
+li.append(3)  # li is now [1, 2, 4, 3] again.
+
+# Access a list like you would any array
+li[0]  # => 1
+# Assign new values to indexes that have already been initialized with =
+li[0] = 42
+li[0]  # => 42
+li[0] = 1  # Note: setting it back to the original value
+# Look at the last element
+li[-1]  # => 3
+
+# Looking out of bounds is an IndexError
+li[4]  # Raises an IndexError
+
+# You can look at ranges with slice syntax.
+# (It's a closed/open range for you mathy types.)
+li[1:3]  # => [2, 4]
+# Omit the beginning
+li[2:]  # => [4, 3]
+# Omit the end
+li[:3]  # => [1, 2, 4]
+# Select every second entry
+li[::2]  # =>[1, 4]
+# Reverse a copy of the list
+li[::-1]  # => [3, 4, 2, 1]
+# Use any combination of these to make advanced slices
+# li[start:end:step]
+
+# Remove arbitrary elements from a list with "del"
+del li[2]  # li is now [1, 2, 3]
+
+# You can add lists
+li + other_li  # => [1, 2, 3, 4, 5, 6]
+# Note: values for li and for other_li are not modified.
+
+# Concatenate lists with "extend()"
+li.extend(other_li)  # Now li is [1, 2, 3, 4, 5, 6]
+
+# Remove first occurrence of a value
+li.remove(2)  # li is now [1, 3, 4, 5, 6]
+li.remove(2)  # Raises a ValueError as 2 is not in the list
+
+# Insert an element at a specific index
+li.insert(1, 2)  # li is now [1, 2, 3, 4, 5, 6] again
+
+# Get the index of the first item found
+li.index(2)  # => 1
+li.index(7)  # Raises a ValueError as 7 is not in the list
+
+# Check for existence in a list with "in"
+1 in li  # => True
+
+# Examine the length with "len()"
+len(li)  # => 6
+
+# Tuples are like lists but are immutable.
+tup = (1, 2, 3)
+tup[0]  # => 1
+tup[0] = 3  # Raises a TypeError
+
+# You can do all those list thingies on tuples too
+len(tup)  # => 3
+tup + (4, 5, 6)  # => (1, 2, 3, 4, 5, 6)
+tup[:2]  # => (1, 2)
+2 in tup  # => True
+
+# You can unpack tuples (or lists) into variables
+a, b, c = (1, 2, 3)  # a is now 1, b is now 2 and c is now 3
+d, e, f = 4, 5, 6  # you can leave out the parentheses
+# Tuples are created by default if you leave out the parentheses
+g = 4, 5, 6  # => (4, 5, 6)
+# Now look how easy it is to swap two values
+e, d = d, e  # d is now 5 and e is now 4
+
+# Dictionaries store mappings
+empty_dict = {}
+# Here is a prefilled dictionary
+filled_dict = {"one": 1, "two": 2, "three": 3}
+
+# Look up values with []
+filled_dict["one"]  # => 1
+
+# Get all keys as a list with "keys()"
+filled_dict.keys()  # => ["three", "two", "one"]
+# Note - Dictionary key ordering is not guaranteed.
+# Your results might not match this exactly.
+
+# Get all values as a list with "values()"
+filled_dict.values()  # => [3, 2, 1]
+# Note - Same as above regarding key ordering.
+
+# Get all key-value pairs as a list of tuples with "items()"
+filled_dict.items()  # => [("one", 1), ("two", 2), ("three", 3)]
+
+# Check for existence of keys in a dictionary with "in"
+"one" in filled_dict  # => True
+1 in filled_dict  # => False
+
+# Looking up a non-existing key is a KeyError
+filled_dict["four"]  # KeyError
+
+# Use "get()" method to avoid the KeyError
+filled_dict.get("one")  # => 1
+filled_dict.get("four")  # => None
+# The get method supports a default argument when the value is missing
+filled_dict.get("one", 4)  # => 1
+filled_dict.get("four", 4)  # => 4
+# note that filled_dict.get("four") is still => None
+# (get doesn't set the value in the dictionary)
+
+# set the value of a key with a syntax similar to lists
+filled_dict["four"] = 4  # now, filled_dict["four"] => 4
+
+# "setdefault()" inserts into a dictionary only if the given key isn't present
+filled_dict.setdefault("five", 5)  # filled_dict["five"] is set to 5
+filled_dict.setdefault("five", 6)  # filled_dict["five"] is still 5
+
+# You can declare sets (which are like unordered lists that cannot contain
+# duplicate values) using the set object.
+empty_set = set()
+# Initialize a "set()" with a bunch of values
+some_set = set([1, 2, 2, 3, 4])  # some_set is now set([1, 2, 3, 4])
+
+# order is not guaranteed, even though it may sometimes look sorted
+another_set = set([4, 3, 2, 2, 1])  # another_set is now set([1, 2, 3, 4])
+
+# Since Python 2.7, {} can be used to declare a set
+filled_set = {1, 2, 2, 3, 4}  # => {1, 2, 3, 4}
+
+# Add more items to a set
+filled_set.add(5)  # filled_set is now {1, 2, 3, 4, 5}
+
+# Do set intersection with &
+other_set = {3, 4, 5, 6}
+filled_set & other_set  # => {3, 4, 5}
+
+# Do set union with |
+filled_set | other_set  # => {1, 2, 3, 4, 5, 6}
+
+# Do set difference with -
+{1, 2, 3, 4} - {2, 3, 5}  # => {1, 4}
+
+# Do set symmetric difference with ^
+{1, 2, 3, 4} ^ {2, 3, 5}  # => {1, 4, 5}
+
+# Check if set on the left is a superset of set on the right
+{1, 2} >= {1, 2, 3}  # => False
+
+# Check if set on the left is a subset of set on the right
+{1, 2} <= {1, 2, 3}  # => True
+
+# Check for existence in a set with in
+2 in filled_set  # => True
+10 in filled_set  # => False
+10 not in filled_set # => True
+
+# Check data type of variable
+type(li)   # => list
+type(filled_dict)   # => dict
+type(5)   # => int
+
+
+####################################################
+#  3. Control Flow
+####################################################
+
+# Let's just make a variable
+some_var = 5
+
+# Here is an if statement. Indentation is significant in python!
+# prints "some_var is smaller than 10"
+if some_var > 10:
+    print "some_var is totally bigger than 10."
+elif some_var < 10:  # This elif clause is optional.
+    print "some_var is smaller than 10."
+else:  # This is optional too.
+    print "some_var is indeed 10."
+
+"""
+For loops iterate over lists
+prints:
+    dog is a mammal
+    cat is a mammal
+    mouse is a mammal
+"""
+for animal in ["dog", "cat", "mouse"]:
+    # You can use {0} to interpolate formatted strings. (See above.)
+    print "{0} is a mammal".format(animal)
+
+"""
+"range(number)" returns a list of numbers
+from zero to the given number
+prints:
+    0
+    1
+    2
+    3
+"""
+for i in range(4):
+    print i
+
+"""
+"range(lower, upper)" returns a list of numbers
+from the lower number to the upper number
+prints:
+    4
+    5
+    6
+    7
+"""
+for i in range(4, 8):
+    print i
+
+"""
+While loops go until a condition is no longer met.
+prints:
+    0
+    1
+    2
+    3
+"""
+x = 0
+while x < 4:
+    print x
+    x += 1  # Shorthand for x = x + 1
+
+# Handle exceptions with a try/except block
+
+# Works on Python 2.6 and up:
+try:
+    # Use "raise" to raise an error
+    raise IndexError("This is an index error")
+except IndexError as e:
+    pass  # Pass is just a no-op. Usually you would do recovery here.
+except (TypeError, NameError):
+    pass  # Multiple exceptions can be handled together, if required.
+else:  # Optional clause to the try/except block. Must follow all except blocks
+    print "All good!"  # Runs only if the code in try raises no exceptions
+finally:  # Execute under all circumstances
+    print "We can clean up resources here"
+
+# Instead of try/finally to cleanup resources you can use a with statement
+with open("myfile.txt") as f:
+    for line in f:
+        print line
+
+
+####################################################
+# 4. Functions
+####################################################
+
+# Use "def" to create new functions
+def add(x, y):
+    print "x is {0} and y is {1}".format(x, y)
+    return x + y  # Return values with a return statement
+
+
+# Calling functions with parameters
+add(5, 6)  # => prints out "x is 5 and y is 6" and returns 11
+
+# Another way to call functions is with keyword arguments
+add(y=6, x=5)  # Keyword arguments can arrive in any order.
+
+
+# You can define functions that take a variable number of
+# positional args, which will be interpreted as a tuple by using *
+def varargs(*args):
+    return args
+
+
+varargs(1, 2, 3)  # => (1, 2, 3)
+
+
+# You can define functions that take a variable number of
+# keyword args, as well, which will be interpreted as a dict by using **
+def keyword_args(**kwargs):
+    return kwargs
+
+
+# Let's call it to see what happens
+keyword_args(big="foot", loch="ness")  # => {"big": "foot", "loch": "ness"}
+
+
+# You can do both at once, if you like
+def all_the_args(*args, **kwargs):
+    print args
+    print kwargs
+
+
+"""
+all_the_args(1, 2, a=3, b=4) prints:
+    (1, 2)
+    {"a": 3, "b": 4}
+"""
+
+# When calling functions, you can do the opposite of args/kwargs!
+# Use * to expand positional args and use ** to expand keyword args.
+args = (1, 2, 3, 4)
+kwargs = {"a": 3, "b": 4}
+all_the_args(*args)  # equivalent to all_the_args(1, 2, 3, 4)
+all_the_args(**kwargs)  # equivalent to all_the_args(a=3, b=4)
+all_the_args(*args, **kwargs)  # equivalent to all_the_args(1, 2, 3, 4, a=3, b=4)
+
+
+# you can pass args and kwargs along to other functions that take args/kwargs
+# by expanding them with * and ** respectively
+def pass_all_the_args(*args, **kwargs):
+    all_the_args(*args, **kwargs)
+    print varargs(*args)
+    print keyword_args(**kwargs)
+
+
+# Function Scope
+x = 5
+
+
+def set_x(num):
+    # Local var x not the same as global variable x
+    x = num  # => 43
+    print x  # => 43
+
+
+def set_global_x(num):
+    global x
+    print x  # => 5
+    x = num  # global var x is now set to 6
+    print x  # => 6
+
+
+set_x(43)
+set_global_x(6)
+
+
+# Python has first class functions
+def create_adder(x):
+    def adder(y):
+        return x + y
+
+    return adder
+
+
+add_10 = create_adder(10)
+add_10(3)  # => 13
+
+# There are also anonymous functions
+(lambda x: x > 2)(3)  # => True
+(lambda x, y: x ** 2 + y ** 2)(2, 1)  # => 5
+
+# There are built-in higher order functions
+map(add_10, [1, 2, 3])  # => [11, 12, 13]
+map(max, [1, 2, 3], [4, 2, 1])  # => [4, 2, 3]
+
+filter(lambda x: x > 5, [3, 4, 5, 6, 7])  # => [6, 7]
+
+# We can use list comprehensions for nice maps and filters
+[add_10(i) for i in [1, 2, 3]]  # => [11, 12, 13]
+[x for x in [3, 4, 5, 6, 7] if x > 5]  # => [6, 7]
+
+# You can construct set and dict comprehensions as well.
+{x for x in 'abcddeef' if x in 'abc'}  # => {'a', 'b', 'c'}
+{x: x ** 2 for x in range(5)}  # => {0: 0, 1: 1, 2: 4, 3: 9, 4: 16}
+
+
+####################################################
+# 5. Classes
+####################################################
+
+# We subclass from object to get a class.
+class Human(object):
+    # A class attribute. It is shared by all instances of this class
+    species = "H. sapiens"
+
+    # Basic initializer, this is called when this class is instantiated.
+    # Note that the double leading and trailing underscores denote objects
+    # or attributes that are used by python but that live in user-controlled
+    # namespaces. You should not invent such names on your own.
+    def __init__(self, name):
+        # Assign the argument to the instance's name attribute
+        self.name = name
+
+        # Initialize property
+        self.age = 0
+
+    # An instance method. All methods take "self" as the first argument
+    def say(self, msg):
+        return "{0}: {1}".format(self.name, msg)
+
+    # A class method is shared among all instances
+    # They are called with the calling class as the first argument
+    @classmethod
+    def get_species(cls):
+        return cls.species
+
+    # A static method is called without a class or instance reference
+    @staticmethod
+    def grunt():
+        return "*grunt*"
+
+    # A property is just like a getter.
+    # It turns the method age() into an read-only attribute
+    # of the same name.
+    @property
+    def age(self):
+        return self._age
+
+    # This allows the property to be set
+    @age.setter
+    def age(self, age):
+        self._age = age
+
+    # This allows the property to be deleted
+    @age.deleter
+    def age(self):
+        del self._age
+
+
+# Instantiate a class
+i = Human(name="Ian")
+print i.say("hi")  # prints out "Ian: hi"
+
+j = Human("Joel")
+print j.say("hello")  # prints out "Joel: hello"
+
+# Call our class method
+i.get_species()  # => "H. sapiens"
+
+# Change the shared attribute
+Human.species = "H. neanderthalensis"
+i.get_species()  # => "H. neanderthalensis"
+j.get_species()  # => "H. neanderthalensis"
+
+# Call the static method
+Human.grunt()  # => "*grunt*"
+
+# Update the property
+i.age = 42
+
+# Get the property
+i.age  # => 42
+
+# Delete the property
+del i.age
+i.age  # => raises an AttributeError
+
+####################################################
+# 6. Modules
+####################################################
+
+# You can import modules
+import math
+
+print math.sqrt(16)  # => 4.0
+
+# You can get specific functions from a module
+from math import ceil, floor
+
+print ceil(3.7)  # => 4.0
+print floor(3.7)  # => 3.0
+
+# You can import all functions from a module.
+# Warning: this is not recommended
+from math import *
+
+# You can shorten module names
+import math as m
+
+math.sqrt(16) == m.sqrt(16)  # => True
+# you can also test that the functions are equivalent
+from math import sqrt
+
+math.sqrt == m.sqrt == sqrt  # => True
+
+# Python modules are just ordinary python files. You
+# can write your own, and import them. The name of the
+# module is the same as the name of the file.
+
+# You can find out which functions and attributes
+# defines a module.
+import math
+
+dir(math)
+
+
+# If you have a Python script named math.py in the same
+# folder as your current script, the file math.py will
+# be loaded instead of the built-in Python module.
+# This happens because the local folder has priority
+# over Python's built-in libraries.
+
+
+####################################################
+# 7. Advanced
+####################################################
+
+# Generators
+# A generator "generates" values as they are requested instead of storing
+# everything up front
+
+# The following method (*NOT* a generator) will double all values and store it
+# in `double_arr`. For large size of iterables, that might get huge!
+def double_numbers(iterable):
+    double_arr = []
+    for i in iterable:
+        double_arr.append(i + i)
+    return double_arr
+
+
+# Running the following would mean we'll double all values first and return all
+# of them back to be checked by our condition
+for value in double_numbers(range(1000000)):  # `test_non_generator`
+    print value
+    if value > 5:
+        break
+
+
+# We could instead use a generator to "generate" the doubled value as the item
+# is being requested
+def double_numbers_generator(iterable):
+    for i in iterable:
+        yield i + i
+
+
+# Running the same code as before, but with a generator, now allows us to iterate
+# over the values and doubling them one by one as they are being consumed by
+# our logic. Hence as soon as we see a value > 5, we break out of the
+# loop and don't need to double most of the values sent in (MUCH FASTER!)
+for value in double_numbers_generator(xrange(1000000)):  # `test_generator`
+    print value
+    if value > 5:
+        break
+
+# BTW: did you notice the use of `range` in `test_non_generator` and `xrange` in `test_generator`?
+# Just as `double_numbers_generator` is the generator version of `double_numbers`
+# We have `xrange` as the generator version of `range`
+# `range` would return back and array with 1000000 values for us to use
+# `xrange` would generate 1000000 values for us as we request / iterate over those items
+
+# Just as you can create a list comprehension, you can create generator
+# comprehensions as well.
+values = (-x for x in [1, 2, 3, 4, 5])
+for x in values:
+    print(x)  # prints -1 -2 -3 -4 -5 to console/terminal
+
+# You can also cast a generator comprehension directly to a list.
+values = (-x for x in [1, 2, 3, 4, 5])
+gen_to_list = list(values)
+print(gen_to_list)  # => [-1, -2, -3, -4, -5]
+
+# Decorators
+# A decorator is a higher order function, which accepts and returns a function.
+# Simple usage example – add_apples decorator will add 'Apple' element into
+# fruits list returned by get_fruits target function.
+def add_apples(func):
+    def get_fruits():
+        fruits = func()
+        fruits.append('Apple')
+        return fruits
+    return get_fruits
+
+@add_apples
+def get_fruits():
+    return ['Banana', 'Mango', 'Orange']
+
+# Prints out the list of fruits with 'Apple' element in it:
+# Banana, Mango, Orange, Apple
+print ', '.join(get_fruits())
+
+# in this example beg wraps say
+# Beg will call say. If say_please is True then it will change the returned
+# message
+from functools import wraps
+
+
+def beg(target_function):
+    @wraps(target_function)
+    def wrapper(*args, **kwargs):
+        msg, say_please = target_function(*args, **kwargs)
+        if say_please:
+            return "{} {}".format(msg, "Please! I am poor :(")
+        return msg
+
+    return wrapper
+
+
+@beg
+def say(say_please=False):
+    msg = "Can you buy me a beer?"
+    return msg, say_please
+
+
+print say()  # Can you buy me a beer?
+print say(say_please=True)  # Can you buy me a beer? Please! I am poor :(
+```
+
+## Ready For More?
+
+### Free Online
+
+* [Automate the Boring Stuff with Python](https://automatetheboringstuff.com)
+* [Learn Python The Hard Way](http://learnpythonthehardway.org/book/)
+* [Dive Into Python](http://www.diveintopython.net/)
+* [The Official Docs](http://docs.python.org/2/)
+* [Hitchhiker's Guide to Python](http://docs.python-guide.org/en/latest/)
+* [Python Module of the Week](http://pymotw.com/2/)
+* [A Crash Course in Python for Scientists](http://nbviewer.ipython.org/5920182)
+* [First Steps With Python](https://realpython.com/learn/python-first-steps/)
+* [LearnPython](http://www.learnpython.org/)
+* [Fullstack Python](https://www.fullstackpython.com/)
+
+### Dead Tree
+
+* [Programming Python](http://www.amazon.com/gp/product/0596158106/ref=as_li_qf_sp_asin_tl?ie=UTF8&camp=1789&creative=9325&creativeASIN=0596158106&linkCode=as2&tag=homebits04-20)
+* [Dive Into Python](http://www.amazon.com/gp/product/1441413022/ref=as_li_tf_tl?ie=UTF8&camp=1789&creative=9325&creativeASIN=1441413022&linkCode=as2&tag=homebits04-20)
+* [Python Essential Reference](http://www.amazon.com/gp/product/0672329786/ref=as_li_tf_tl?ie=UTF8&camp=1789&creative=9325&creativeASIN=0672329786&linkCode=as2&tag=homebits04-20)