a =
print str(a).decode('string_escape')
# 輸出:
a = ["a", "b", "c"]
b = dict.fromkeys(a)
print b
# 輸出:
a = ["a", "b", "c"]
b = dict.fromkeys(a, 250)
print b
# 輸出:
import collections
data = collections.ordereddict()
data["a"] = "1"
data["b"] = "2"
data["c"] = "3"
print data
# 輸出:ordereddict([('a', '1'), ('b', '2'), ('c', '3')])
import json
from collections import ordereddict
jsonstr = ''
configdict = json.loads(jsonstr, object_pairs_hook=ordereddict)
print configdict
# 輸出:ordereddict([(u'a', 1), (u'b', 2), (u'c', 3)])
a =
print(a['a'])
# 輸出:123
a =
print(a.get('e'))
# 輸出:none
a =
print(a.get('key', '404'))
# 輸出:404
a =
print a.keys()
# 輸出:['a', 'c', 'b', 'd']
a =
print str(a.values()).decode('string_escape')
# 輸出: [123, 'pen', 456, '嘿嘿']
a =
if 'a' in a:
print('yes')
# 輸出:yes
a =
for k, v in a.items():
print str((k, v)).decode('string_escape')
# 輸出:
# ('a', 123)
# ('c', 'pen')
# ('b', 456)
# ('d', '嘿嘿')
a =
for kv in a.items():
print str(kv).decode('string_escape')
# 輸出:
# ('a', 123)
# ('c', 'pen')
# ('b', 456)
# ('d', '嘿嘿')
a =
for k in a:
print str((k, a[k])).decode('string_escape')
print str((k, a.get(k))).decode('string_escape')
# 輸出:
# ('a', 123)
# ('a', 123)
# ('c', 'pen')
# ('c', 'pen')
# ('b', 456)
# ('b', 456)
# ('d', '嘿嘿')
# ('d', '嘿嘿')
a =
a['e'] = 250
print str(a).decode('string_escape')
# 輸出:
a['a'] = "hehe"
print str(a).decode('string_escape')
# 輸出:
a =
a.setdefault('a', 250)
print str(a).decode('string_escape')
# 輸出:
a =
a.setdefault('e', 250)
print str(a).decode('string_escape')
# 輸出:
a =
a.setdefault('f')
print str(a).decode('string_escape')
# 輸出:
a =
b =
a.update(b)
print str(a).decode('string_escape')
# 輸出:
a =
del a["d"]
print a
# 輸出:
a =
b = a.pop("a")
print a
# 輸出:
print b
# 輸出:123
a =
b = a.popitem()
print a
# 輸出:
print b
# 輸出:('a', 123)
a =
b = a.clear()
print a
# 輸出:{}
a =
print a.has_key("a")
# 輸出:true
a =
print a.items()
# 輸出:[('a', 123), ('c', 'pen'), ('b', 456)]
print(list(a.items()))
# 輸出:[('a', 123), ('c', 'pen'), ('b', 456)]
a =
print len(a)
# 輸出:3
a =
print str(a)
print type(str(a))
# 輸出:
# 輸出:
import json
a =
print json.dumps(a)
# 輸出:
print type(json.dumps(a))
# 輸出:
import json
a = ''
print json.loads(a)
# 輸出:
print type(json.loads(a))
# 輸出:
淺拷貝: 引用物件
淺拷貝:深拷貝父物件(一級目錄),子物件(二級目錄)不拷貝,還是引用
a =
b = a
c = a.copy()
# 修改 data 資料
a['user'] = 'root'
a['num'].remove(1)
print(a)
# # 輸出:
print(b)
# # 輸出:
print(c)
# # 輸出:
import copy
a =
b = copy.deepcopy(a)
# 修改 data 資料
a['user'] = 'root'
a['num'].remove(1)
print a
# # 輸出:
print b
# 輸出:
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