#
#	Python dict: iteration
#
person_1 = {
    'name': 'Jane', 
    'dob': '12/08/1997', 
    'city': 'Houston',
	'university': 'UHCL'
}

print("""dict methods for iteration.
    dict_1.keys(): Returns a view object of all keys.
    dict_1.values(): Returns a view object of all values.
    dict_1.items(): Returns a view object of all key-value pairs.
""")

print(f"person_1: {person_1}")
print(f"person_1.keys(): {person_1.keys()}")

#  dict_keys(['name', 'dob', 'city', 'university']):
#       dict_keys: name of object; a view object of all keys,
#           object contains one list of keys in the dict.
print(f"person_1.values(): {person_1.values()}")
print(f"person_1.items(): {person_1.items()}")

# dict_items([('name', 'Jane'), ('dob', '12/08/1997'), ('city', 'Houston'), ('university', 'UHCL')])
#   ('name', 'Jane'): a tuple of 2 items: a key and a value.
#   (): tuple: immutable
#   []: list: mutable.
print("""view objects are dynamic and live. 
They are views/windows on the underlying dict.
""")
print("keys = person_1.keys()")
keys = person_1.keys()

print(f"keys: {keys}")
print("person_1['hobbies'] = {'primary': 'music', 'others': ['games', 'woodwork']}")
person_1['hobbies'] = {'primary': 'music', 'others': ['games', 'woodwork']}
print(f"person_1: {person_1}")
print(f"keys: {keys}")

#   iterations to pretty print a dict.
print()
print(f"person_1: {person_1}")

print("""
print('{')
for key in person_1.keys():
    print(f"    {key}: {person_1[key]}")
print('}')
""")
print('{')
for key in person_1.keys():
    print(f"    {key}: {person_1[key]}")
print('}')

print("""
print('{')
for key, value in person_1.items():
    print(f"    {key}: {value}")
print('}')
""")
print('{')
for key, value in person_1.items():
    print(f"    {key}: {value}")
print('}')

print("""
import pprint
pprint.pp(person_1, indent=4)
""")

import pprint
pprint.pp(person_1, indent=4)

print()
print("pprint.pp(person_1, indent=4, sort_dicts=True)")
pprint.pp(person_1, indent=4, sort_dicts=True)

print("""
#   simple summing use cases.
sales_by_region = {
    'North': 1120, 
    'South': 2100, 
    'East': 3219, 
    'West': 4050}
total_sales = 0
for sales_amount in sales_by_region.values():
    total_sales += sales_amount
print(f"Total sales across all regions: {total_sales}")""")
#   simple summing use cases.
sales_by_region = {
    'North': 1120, 
    'South': 2100, 
    'East': 3219, 
    'West': 4050}
total_sales = 0
for sales_amount in sales_by_region.values():
    total_sales += sales_amount
print(f"Total sales across all regions: {total_sales}") 
 
# version #2:
print('print(f"Total sales across all regions: {sum(sales_by_region.values())}")')
print(f"Total sales across all regions: {sum(sales_by_region.values())}")