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Given the following text description, write Python code to implement the functionality described below step by step
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Description:
 print "hello astronomy"
Step1:  Note
Step2:  This behavior might seem confusing if you're wrongly thinking of variables as buckets that contain data. But if you're correctly thinking of variables as pointers to objects, then this behavior makes sense.
Note also that if we use "=" to assign another value to x, this will not affect the value of y – assignment is simply a change of what object the variable points to
Step3:  Python integers are variable-precision, so you can do computations that would overflow in other languages
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Python Code:
# set the midpoint
midpoint = 25
# make two empty lists
lower = []; upper = []
# split the numbers into lower and upper
for i in range(50):
    if (i < midpoint):
        lower.append(i)
        # print("i lower = ",i)
    else:
        upper.append(i)
        # print("i upper = ",i)
        
print "lower:", lower
print "upper:", upper
Explanation: print "hello astronomy"
End of explanation
x = 1         # x is an integer
x = 'hello'   # now x is a string
x = [1, 2, 3] # now x is a list
# All python variables are pointers, so if we have two variable pointing to same mutable object, then changing
# one will change other as well.
x = [1, 2, 3]
y = x
# both x and y are pointing to same object
print y
x.append(4) # append 4 to the list pointed to by x
print y # y's list is modified as well!
Explanation: Note: Most widely used style guide in Python is known as PEP8, and can be found at https://www.python.org/dev/peps/pep-0008/.
Python is dynamically-typed: variable names can point to objects of any type:
End of explanation
x = 'something else'
print(y)  # y is unchanged because now x is pointing to other object, but the previously pointed object is not changed
#Everything is Object
x = 'A string'
type(x)
x = 89
type(x)
x = 89.25
type(x)
#converting decimal to binary
print "binary 10:", bin(10)
# OR operation
print "4 OR 10:  ", bin(4 | 10)
-1 == ~0
1 in [1, 2, 3]
2 not in [1, 2, 3]
Explanation: This behavior might seem confusing if you're wrongly thinking of variables as buckets that contain data. But if you're correctly thinking of variables as pointers to objects, then this behavior makes sense.
Note also that if we use "=" to assign another value to x, this will not affect the value of y – assignment is simply a change of what object the variable points to:
End of explanation
2 ** 200
for i in range(2):
    print(i)
i = 0
while i < 2:
    print(i)
    i += 1
def _fibonacci(N,a=0,b=1):
    try:
        if N < 0:
            raise ValueError #if not raised, this program will not raise any error,insted blank vector will be returned
        L = []
        # a, b = 0, 1 #getting a and b as default arguments
        while len(L) < N:
            a, b = b, a + b
            L.append(a)
        return L
    except ValueError:
        print "ValueError : N must be non-negative"
        
_fibonacci(10)
_fibonacci(-10)
def catch_all(*args, **kwargs):
    print("args =", args)
    print("kwargs = ", kwargs)
catch_all(1, 2, 3, a=4, b=5)
data = [{'first':'Guido', 'last':'Van Rossum', 'YOB':1956},
        {'first':'Grace', 'last':'Hopper',     'YOB':1906},
        {'first':'Alan',  'last':'Turing',     'YOB':1912}]
# sort alphabetically by first name
sorted(data, key=lambda item: item['first'])
def safe_divide(a, b):
    try: #try
        return a / b
    except ZeroDivisionError: # catch
        print "ZeroDivisionError occoured and caught"
        return 1E100
    except TypeError:
        print "TypeError occoured and caught"
safe_divide(1, 2) #no error
safe_divide(2, 0) #ZeroDivisionError
safe_divide(2,'str') #TypeError
Explanation: Python integers are variable-precision, so you can do computations that would overflow in other languages:
End of explanation
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