The document discusses various methods for dictionaries in Python including: - dict() to create an empty dictionary or initialize with key-value pairs - clear() to remove all items from a dictionary - copy() to make a shallow copy of a dictionary - get() to return a value for a given key or a default if the key does not exist - has_key() to check if a dictionary contains a given key - items() to return a list of all key-value pairs as tuples - iteritems() to iterate over key-value pairs

1. Pyhon
dict()
Алексей Бованенко
a.bovanenko@gmail.com

2. python dict()
● d = dict()
● d = {'key1':'value1', 'key2':'value2'}
● d1 = dict(d)
● d2 = dict()
for i in range(5):
d2[i] = ‘value’+str(i)

3. python dict clear()
● clear() -> None
● d = {‘key1’: ‘value1’, ‘key2’: ‘value2’}
● d.clear()
○ {}

4. python dict copy()
● d = {‘key1’: ‘value1’, ‘key2’: ‘value2’}
● d_copy = d.copy()
● d_copy
○ {‘key1’: ‘value1’, ‘key2’: ‘value2’}

5. python dict get()
● get(k[,v]) -> d[k] if k in d, else v. v defaults to None
● d = {'key1':'value1', 'key2':'value2'}
● d.get('key3')
○ ‘’
● d.get('key2')
○ 'value2'

6. python dict has_key()
● has_key(k) -> True if D has a key k, else False
● d = {'key1':'value1', 'key2':'value2'}
● d.has_key(‘key2’)
○ True
● d.has_key(‘key3’)
○ False

7. python dict items()
● items() -> list of D's (key, value) pairs
● d.items()
○ [('key2', 'value2'), ('key1', 'value1')]
● for p in d.items(): # for (k,v) in d.items():
print p[0], p[1] # print k, v
○ key2 value2
○ key1 value1

8. python dict iteritems()
● iteritems() -> an iterator over the (key, val) items of d
● for (k,v) in d.iteritems():
print k,v

9. Спасибо за внимание
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