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Python: Input-Output (Solutions)
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Raw input
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#. Solution::

    food = raw_input("What is your favourite food? ")

    print "I also like", food

#. Solution::

    a_and_b = raw_input("Write two integers: ")
    words = a_and_b.split()
    a = int(words[0])
    b = int(words[1])

    answer = raw_input("how much is " + str(a) + " " + str(b) " ? ")
    result = int(answer)

    print a + b == answer

#. Solution::

    key = raw_input("give me a key: ")
    value = raw_input("give me a value: ")

    dictionary = {key: value}
    # or
    dictionary = {}
    dictionary[key] = value

    print "dictionary =", dictionary

#. Solution::

    name = raw_input("Give me your full name: ")

    fixed_words = [word[0].upper() + word[1:].lower()
                         for word in name.split()]
    print "Your name is:", " ".join(fixed_words)

Filesystem
----------------------

#. Solution::

    f = open("data/aatable", "r")
    # or
    f = open("data/aatable")

    rows = f.readlines()
    print type(rows)                           # list
    print type(rows[0])                        # str
    print len(rows)

    f.close()

#. Solution::

    f = open("data/aatable")

    first_row = f.readline()
    print "The first row is: ", first_row

    remaining_rows = f.readlines()
    print "another", len(remaining_rows), " rows are left"

    remaining_rows_bis = f.readlines()
    print "then, another", len(remaining_rows_bis), "rows are left"

    # In the last case, 0 rows should be left: the first
    # readlines() already read all the lines of f

    f.close()

#. Solution::

    f = open("output.txt", "w")
    f.write("check one two three check")
    f.close()

    g = open("output.txt", "r")
    print g.readlines()
    g.close()

#. Solution::

    verses = [
        "S'i fosse fuoco, arderei 'l mondo"
        "s'i fosse vento, lo tempestarei"
    ]

    f = open("poetry.txt", "w")
    f.write("\n".join(verses))
    f.close()

   Now let's try with ``"a"``::

    f2 = open("poetry2.txt", "a")
    f2.write(verses[0] + "\n")
    f2.close()

    f2 = open("poetry2.txt", "a")
    f2.write(verses[1] + "\n")
    f2.close()

   And if we use ``"w"`` on ``"poetry2.txtx"``::

    f = open("poetry2.txt", "w")
    # Here we do absolutely nothing to f, we just close it
    f.close()

   we can see that now ``"poetry2.txt"`` is empty! This happens
   as a consequence of using ``"w"`` instead of ``"a"``.

#. Let's write in the file ``trick.py``::

    myself = open("trick.py")
    print myself.read()
    myself.close()

   Let's execute the file to verify that it's working as we want: from a shell, let's write::

    python trick.py