remove comment specific to python2

source/Data_Types.rst

@@ -40,23 +40,16 @@ Use the Python interpreter to check your answers. ::
    8.5
    >>> height / 3
    4.0
-   >>> # one of the operand is a float (2.0 or height) then python pyhton perform afloat  division but keep in mind that float numbers are aproximation.
-   >>> # if you need precision you need to use Decimal. But operations on Decimal are slow and float offer quite enought precision
+   >>> # one of the operand is a float (2.0 or height) then python pyhton perform a float division but keep in mind that float numbers are approximation.
+   >>> # if you need precision you need to use Decimal. But operations on Decimal are slow and float offer quite enough precision
    >>> # so we use decimal only if wee need great precision
    >>> # Euclidian division
-   >>> 2 / 3
+   >>> 2 // 3
    0
    >>> # float division
-   >>> float(2)/float(3)
+   >>> 2 / 3
    0.6666666666666666
-   >>> # decimal division
-   >>> from decimal import Decimal
-   >>> a = Decimal(2)
-   >>> b = Decimal(3)
-   >>> a / b
-   Decimal('0.6666666666666666666666666667')
-   >>> 1 + 2 * 5
-   11
+
 
 
 Exercise
@@ -76,9 +69,7 @@ after that, you can use ``math.pi`` everywhere in the file like this::
       >>>
       >>> #do what you need to do
       >>> math.pi #use math.pi
-   
-**Hint**: the volume of a spher with radius 5 is **not** 392.7 !
-   
+
 .. literalinclude:: _static/code/vol_of_sphere.py
    :linenos:
    :language: python
@@ -257,9 +248,10 @@ for the enzymes which have a recognition site can you give their positions? ::
    
 is there only one site in sv40 per enzyme? 
 
-The ``find`` method give the index of the first occurence or -1 if the substring is not found.
-So we can not determine the occurence of a site only with the find method.
-We will see how to do that when we learn looping and conditions. 
+The ``find`` method give the index of the first occurrence or -1 if the substring is not found.
+So we can not determine the occurrences of a site only with the find method.
+We can know how many sites are present with the ``count`` method.
+We will see how to determine the site of all occurrences when we learn looping and conditions.
 
 
 Exercise
@@ -381,14 +373,8 @@ use sv40 sequence to test your function.
    >>> 
    >>> sequence = fasta_to_one_line(sv40)
    >>> gc_pc = gc_percent(sequence)
-   >>> report = the sv40 is {0} bp length and have {1:.2%} gc".format(len(sequence), gc_pc)
+   >>> report = "the sv40 is {0} bp length and have {1:.2%} gc".format(len(sequence), gc_pc)
    >>> print report
    'the sv40 is 5243 bp length and have 40.80% gc'
    
 :download:`gc_percent.py <_static/code/gc_percent.py>` . 
-
-
-::
-
-   gc_pc =  float(sv40_sequence.count('g') + sv40_sequence.count('c')) / float(len(sv40_sequence))
-   "the sv40 is {0} bp lenght and have {1:.2%} gc".format(len(sv40), gc_pc)
\ No newline at end of file