摘要:本文是對于現代開發語法基礎與工程實踐的總結,更多相關資料參考學習與實踐資料索引本文參考了,等。
本文是對于 現代 Python 開發:語法基礎與工程實踐的總結,更多 Python 相關資料參考 Python 學習與實踐資料索引;本文參考了 Python Crash Course - Cheat Sheets,pysheeet 等。本文僅包含筆者在日常工作中經常使用的,并且認為較為關鍵的知識點與語法,如果想要進一步學習 Python 相關內容或者對于機器學習與數據挖掘方向感興趣,可以參考程序猿的數據科學與機器學習實戰手冊。
基礎語法Python 是一門高階、動態類型的多范式編程語言;定義 Python 文件的時候我們往往會先聲明文件編碼方式:
# 指定腳本調用方式 #!/usr/bin/env python # 配置 utf-8 編碼 # -*- coding: utf-8 -*- # 配置其他編碼 # -*- coding:-*- # Vim 中還可以使用如下方式 # vim:fileencoding=
人生苦短,請用 Python,大量功能強大的語法糖的同時讓很多時候 Python 代碼看上去有點像偽代碼。譬如我們用 Python 實現的簡易的快排相較于 Java 會顯得很短小精悍:
def quicksort(arr): if len(arr) <= 1: return arr pivot = arr[len(arr) / 2] left = [x for x in arr if x < pivot] middle = [x for x in arr if x == pivot] right = [x for x in arr if x > pivot] return quicksort(left) + middle + quicksort(right) print quicksort([3,6,8,10,1,2,1]) # Prints "[1, 1, 2, 3, 6, 8, 10]"控制臺交互
可以根據 __name__ 關鍵字來判斷是否是直接使用 python 命令執行某個腳本,還是外部引用;Google 開源的 fire 也是不錯的快速將某個類封裝為命令行工具的框架:
import fire class Calculator(object): """A simple calculator class.""" def double(self, number): return 2 * number if __name__ == "__main__": fire.Fire(Calculator) # python calculator.py double 10 # 20 # python calculator.py double --number=15 # 30
Python 2 中 print 是表達式,而 Python 3 中 print 是函數;如果希望在 Python 2 中將 print 以函數方式使用,則需要自定義引入:
from __future__ import print_function
我們也可以使用 pprint 來美化控制臺輸出內容:
import pprint stuff = ["spam", "eggs", "lumberjack", "knights", "ni"] pprint.pprint(stuff) # 自定義參數 pp = pprint.PrettyPrinter(depth=6) tup = ("spam", ("eggs", ("lumberjack", ("knights", ("ni", ("dead",("parrot", ("fresh fruit",)))))))) pp.pprint(tup)模塊
Python 中的模塊(Module)即是 Python 源碼文件,其可以導出類、函數與全局變量;當我們從某個模塊導入變量時,函數名往往就是命名空間(Namespace)。而 Python 中的包(Package)則是模塊的文件夾,往往由 __init__.py 指明某個文件夾為包:
# 文件目錄 someDir/ main.py siblingModule.py # siblingModule.py def siblingModuleFun(): print("Hello from siblingModuleFun") def siblingModuleFunTwo(): print("Hello from siblingModuleFunTwo") import siblingModule import siblingModule as sibMod sibMod.siblingModuleFun() from siblingModule import siblingModuleFun siblingModuleFun() try: # Import "someModuleA" that is only available in Windows import someModuleA except ImportError: try: # Import "someModuleB" that is only available in Linux import someModuleB except ImportError:
Package 可以為某個目錄下所有的文件設置統一入口:
someDir/ main.py subModules/ __init__.py subA.py subSubModules/ __init__.py subSubA.py # subA.py def subAFun(): print("Hello from subAFun") def subAFunTwo(): print("Hello from subAFunTwo") # subSubA.py def subSubAFun(): print("Hello from subSubAFun") def subSubAFunTwo(): print("Hello from subSubAFunTwo") # __init__.py from subDir # Adds "subAFun()" and "subAFunTwo()" to the "subDir" namespace from .subA import * # The following two import statement do the same thing, they add "subSubAFun()" and "subSubAFunTwo()" to the "subDir" namespace. The first one assumes "__init__.py" is empty in "subSubDir", and the second one, assumes "__init__.py" in "subSubDir" contains "from .subSubA import *". # Assumes "__init__.py" is empty in "subSubDir" # Adds "subSubAFun()" and "subSubAFunTwo()" to the "subDir" namespace from .subSubDir.subSubA import * # Assumes "__init__.py" in "subSubDir" has "from .subSubA import *" # Adds "subSubAFun()" and "subSubAFunTwo()" to the "subDir" namespace from .subSubDir import * # __init__.py from subSubDir # Adds "subSubAFun()" and "subSubAFunTwo()" to the "subSubDir" namespace from .subSubA import * # main.py import subDir subDir.subAFun() # Hello from subAFun subDir.subAFunTwo() # Hello from subAFunTwo subDir.subSubAFun() # Hello from subSubAFun subDir.subSubAFunTwo() # Hello from subSubAFunTwo表達式與控制流 條件選擇
Python 中使用 if、elif、else 來進行基礎的條件選擇操作:
if x < 0: x = 0 print("Negative changed to zero") elif x == 0: print("Zero") else: print("More")
Python 同樣支持 ternary conditional operator:
a if condition else b
也可以使用 Tuple 來實現類似的效果:
# test 需要返回 True 或者 False (falseValue, trueValue)[test] # 更安全的做法是進行強制判斷 (falseValue, trueValue)[test == True] # 或者使用 bool 類型轉換函數 (falseValue, trueValue)[bool(循環遍歷)]
for-in 可以用來遍歷數組與字典:
words = ["cat", "window", "defenestrate"] for w in words: print(w, len(w)) # 使用數組訪問操作符,能夠迅速地生成數組的副本 for w in words[:]: if len(w) > 6: words.insert(0, w) # words -> ["defenestrate", "cat", "window", "defenestrate"]
如果我們希望使用數字序列進行遍歷,可以使用 Python 內置的 range 函數:
a = ["Mary", "had", "a", "little", "lamb"] for i in range(len(a)): print(i, a[i])基本數據類型
可以使用內建函數進行強制類型轉換(Casting):
int(str) float(str) str(int) str(float)Number: 數值類型
x = 3 print type(x) # Prints "布爾類型" print x # Prints "3" print x + 1 # Addition; prints "4" print x - 1 # Subtraction; prints "2" print x * 2 # Multiplication; prints "6" print x ** 2 # Exponentiation; prints "9" x += 1 print x # Prints "4" x *= 2 print x # Prints "8" y = 2.5 print type(y) # Prints " " print y, y + 1, y * 2, y ** 2 # Prints "2.5 3.5 5.0 6.25"
Python 提供了常見的邏輯操作符,不過需要注意的是 Python 中并沒有使用 &&、|| 等,而是直接使用了英文單詞。
t = True f = False print type(t) # Prints "String: 字符串" print t and f # Logical AND; prints "False" print t or f # Logical OR; prints "True" print not t # Logical NOT; prints "False" print t != f # Logical XOR; prints "True"
Python 2 中支持 Ascii 碼的 str() 類型,獨立的 unicode() 類型,沒有 byte 類型;而 Python 3 中默認的字符串為 utf-8 類型,并且包含了 byte 與 bytearray 兩個字節類型:
type("Guido") # string type is str in python2 ## 使用 __future__ 中提供的模塊來降級使用 Unicode from __future__ import unicode_literals type("Guido") # string type become unicode #
Python 字符串支持分片、模板字符串等常見操作:
var1 = "Hello World!" var2 = "Python Programming" print "var1[0]: ", var1[0] print "var2[1:5]: ", var2[1:5] # var1[0]: H # var2[1:5]: ytho print "My name is %s and weight is %d kg!" % ("Zara", 21) # My name is Zara and weight is 21 kg!
str[0:4] len(str) string.replace("-", " ") ",".join(list) "hi {0}".format("j") str.find(",") str.index(",") # same, but raises IndexError str.count(",") str.split(",") str.lower() str.upper() str.title() str.lstrip() str.rstrip() str.strip() str.islower()
# 移除所有的特殊字符 re.sub("[^A-Za-z0-9]+", "", mystring)
如果需要判斷是否包含某個子字符串,或者搜索某個字符串的下標:
# in 操作符可以判斷字符串 if "blah" not in somestring: continue # find 可以搜索下標 s = "This be a string" if s.find("is") == -1: print "No "is" here!" else: print "Found "is" in the string."Regex: 正則表達式
import re # 判斷是否匹配 re.match(r"^[aeiou]", str) # 以第二個參數指定的字符替換原字符串中內容 re.sub(r"^[aeiou]", "?", str) re.sub(r"(xyz)", r"1", str) # 編譯生成獨立的正則表達式對象 expr = re.compile(r"^...$") expr.match(...) expr.sub(...)
下面列舉了常見的表達式使用場景:
# 檢測是否為 HTML 標簽 re.search("<[^/>][^>]*>", "") # 常見的用戶名密碼 re.match("^[a-zA-Z0-9-_]{3,16}$", "Foo") is not None re.match("^w|[-_]{3,16}$", "Foo") is not None # Email re.match("^([a-z0-9_.-]+)@([da-z.-]+).([a-z.]{2,6})$", "hello.world@example.com") # Url exp = re.compile(r"""^(https?://)? # match http or https ([da-z.-]+) # match domain .([a-z.]{2,6}) # match domain ([/w .-]*)/?$ # match api or file """, re.X) exp.match("www.google.com") # IP 地址 exp = re.compile(r"""^(?:(?:25[0-5] |2[0-4][0-9] |[1]?[0-9][0-9]?).){3} (?:25[0-5] |2[0-4][0-9] |[1]?[0-9][0-9]?)$""", re.X) exp.match("192.168.1.1")集合類型 List: 列表 Operation: 創建增刪
list 是基礎的序列類型:
l = [] l = list() # 使用字符串的 split 方法,可以將字符串轉化為列表 str.split(".") # 如果需要將數組拼裝為字符串,則可以使用 join list1 = ["1", "2", "3"] str1 = "".join(list1) # 如果是數值數組,則需要先進行轉換 list1 = [1, 2, 3] str1 = "".join(str(e) for e in list1)
可以使用 append 與 extend 向數組中插入元素或者進行數組連接
x = [1, 2, 3] x.append([4, 5]) # [1, 2, 3, [4, 5]] x.extend([4, 5]) # [1, 2, 3, 4, 5],注意 extend 返回值為 None
可以使用 pop、slices、del、remove 等移除列表中元素:
myList = [10,20,30,40,50] # 彈出第二個元素 myList.pop(1) # 20 # myList: myList.pop(1) # 如果不加任何參數,則默認彈出最后一個元素 myList.pop() # 使用 slices 來刪除某個元素 a = [ 1, 2, 3, 4, 5, 6 ] index = 3 # Only Positive index a = a[:index] + a[index+1 :] # 根據下標刪除元素 myList = [10,20,30,40,50] rmovIndxNo = 3 del myList[rmovIndxNo] # myList: [10, 20, 30, 50] # 使用 remove 方法,直接根據元素刪除 letters = ["a", "b", "c", "d", "e"] numbers.remove(numbers[1]) print(*letters) # used a * to make it unpack you don"t have toIteration: 索引遍歷
你可以使用基本的 for 循環來遍歷數組中的元素,就像下面介個樣紙:
animals = ["cat", "dog", "monkey"] for animal in animals: print animal # Prints "cat", "dog", "monkey", each on its own line.
如果你在循環的同時也希望能夠獲取到當前元素下標,可以使用 enumerate 函數:
animals = ["cat", "dog", "monkey"] for idx, animal in enumerate(animals): print "#%d: %s" % (idx + 1, animal) # Prints "#1: cat", "#2: dog", "#3: monkey", each on its own line
Python 也支持切片(Slices):
nums = range(5) # range is a built-in function that creates a list of integers print nums # Prints "[0, 1, 2, 3, 4]" print nums[2:4] # Get a slice from index 2 to 4 (exclusive); prints "[2, 3]" print nums[2:] # Get a slice from index 2 to the end; prints "[2, 3, 4]" print nums[:2] # Get a slice from the start to index 2 (exclusive); prints "[0, 1]" print nums[:] # Get a slice of the whole list; prints ["0, 1, 2, 3, 4]" print nums[:-1] # Slice indices can be negative; prints ["0, 1, 2, 3]" nums[2:4] = [8, 9] # Assign a new sublist to a slice print nums # Prints "[0, 1, 8, 9, 4]"Comprehensions: 變換
Python 中同樣可以使用 map、reduce、filter,map 用于變換數組:
# 使用 map 對數組中的每個元素計算平方 items = [1, 2, 3, 4, 5] squared = list(map(lambda x: x**2, items)) # map 支持函數以數組方式連接使用 def multiply(x): return (x*x) def add(x): return (x+x) funcs = [multiply, add] for i in range(5): value = list(map(lambda x: x(i), funcs)) print(value)
reduce 用于進行歸納計算:
# reduce 將數組中的值進行歸納 from functools import reduce product = reduce((lambda x, y: x * y), [1, 2, 3, 4]) # Output: 24
filter 則可以對數組進行過濾:
number_list = range(-5, 5) less_than_zero = list(filter(lambda x: x < 0, number_list)) print(less_than_zero) # Output: [-5, -4, -3, -2, -1]字典類型 創建增刪
d = {"cat": "cute", "dog": "furry"} # 創建新的字典 print d["cat"] # 字典不支持點(Dot)運算符取值
如果需要合并兩個或者多個字典類型:
# python 3.5 z = {**x, **y} # python 2.7 def merge_dicts(*dict_args): """ Given any number of dicts, shallow copy and merge into a new dict, precedence goes to key value pairs in latter dicts. """ result = {} for dictionary in dict_args: result.update(dictionary) return result索引遍歷
可以根據鍵來直接進行元素訪問:
# Python 中對于訪問不存在的鍵會拋出 KeyError 異常,需要先行判斷或者使用 get print "cat" in d # Check if a dictionary has a given key; prints "True" # 如果直接使用 [] 來取值,需要先確定鍵的存在,否則會拋出異常 print d["monkey"] # KeyError: "monkey" not a key of d # 使用 get 函數則可以設置默認值 print d.get("monkey", "N/A") # Get an element with a default; prints "N/A" print d.get("fish", "N/A") # Get an element with a default; prints "wet" d.keys() # 使用 keys 方法可以獲取所有的鍵
可以使用 for-in 來遍歷數組:
# 遍歷鍵 for key in d: # 比前一種方式慢 for k in dict.keys(): ... # 直接遍歷值 for value in dict.itervalues(): ... # Python 2.x 中遍歷鍵值 for key, value in d.iteritems(): # Python 3.x 中遍歷鍵值 for key, value in d.items():其他序列類型 集合
# Same as {"a", "b","c"} normal_set = set(["a", "b","c"]) # Adding an element to normal set is fine normal_set.add("d") print("Normal Set") print(normal_set) # A frozen set frozen_set = frozenset(["e", "f", "g"]) print("Frozen Set") print(frozen_set) # Uncommenting below line would cause error as # we are trying to add element to a frozen set # frozen_set.add("h")函數 函數定義
Python 中的函數使用 def 關鍵字進行定義,譬如:
def sign(x): if x > 0: return "positive" elif x < 0: return "negative" else: return "zero" for x in [-1, 0, 1]: print sign(x) # Prints "negative", "zero", "positive"
Python 支持運行時創建動態函數,也即是所謂的 lambda 函數:
def f(x): return x**2 # 等價于 g = lambda x: x**2參數 Option Arguments: 不定參數
def example(a, b=None, *args, **kwargs): print a, b print args print kwargs example(1, "var", 2, 3, word="hello") # 1 var # (2, 3) # {"word": "hello"} a_tuple = (1, 2, 3, 4, 5) a_dict = {"1":1, "2":2, "3":3} example(1, "var", *a_tuple, **a_dict) # 1 var # (1, 2, 3, 4, 5) # {"1": 1, "2": 2, "3": 3}生成器
def simple_generator_function(): yield 1 yield 2 yield 3 for value in simple_generator_function(): print(value) # 輸出結果 # 1 # 2 # 3 our_generator = simple_generator_function() next(our_generator) # 1 next(our_generator) # 2 next(our_generator) #3 # 生成器典型的使用場景譬如無限數組的迭代 def get_primes(number): while True: if is_prime(number): yield number number += 1裝飾器
裝飾器是非常有用的設計模式:
# 簡單裝飾器 from functools import wraps def decorator(func): @wraps(func) def wrapper(*args, **kwargs): print("wrap function") return func(*args, **kwargs) return wrapper @decorator def example(*a, **kw): pass example.__name__ # attr of function preserve # "example" # Decorator # 帶輸入值的裝飾器 from functools import wraps def decorator_with_argument(val): def decorator(func): @wraps(func) def wrapper(*args, **kwargs): print "Val is {0}".format(val) return func(*args, **kwargs) return wrapper return decorator @decorator_with_argument(10) def example(): print "This is example function." example() # Val is 10 # This is example function. # 等價于 def example(): print "This is example function." example = decorator_with_argument(10)(example) example() # Val is 10 # This is example function.類與對象 類定義
Python 中對于類的定義也很直接:
class Greeter(object): # Constructor def __init__(self, name): self.name = name # Create an instance variable # Instance method def greet(self, loud=False): if loud: print "HELLO, %s!" % self.name.upper() else: print "Hello, %s" % self.name g = Greeter("Fred") # Construct an instance of the Greeter class g.greet() # Call an instance method; prints "Hello, Fred" g.greet(loud=True) # Call an instance method; prints "HELLO, FRED!"
# isinstance 方法用于判斷某個對象是否源自某個類 ex = 10 isinstance(ex,int)Managed Attributes: 受控屬性
# property、setter、deleter 可以用于復寫點方法 class Example(object): def __init__(self, value): self._val = value @property def val(self): return self._val @val.setter def val(self, value): if not isintance(value, int): raise TypeError("Expected int") self._val = value @val.deleter def val(self): del self._val @property def square3(self): return 2**3 ex = Example(123) ex.val = "str" # Traceback (most recent call last): # File "", line 1, in # File "test.py", line 12, in val # raise TypeError("Expected int") # TypeError: Expected int類方法與靜態方法
class example(object): @classmethod def clsmethod(cls): print "I am classmethod" @staticmethod def stmethod(): print "I am staticmethod" def instmethod(self): print "I am instancemethod" ex = example() ex.clsmethod() # I am classmethod ex.stmethod() # I am staticmethod ex.instmethod() # I am instancemethod example.clsmethod() # I am classmethod example.stmethod() # I am staticmethod example.instmethod() # Traceback (most recent call last): # File "", line 1, in # TypeError: unbound method instmethod() ...對象 實例化 屬性操作
Python 中對象的屬性不同于字典鍵,可以使用點運算符取值,直接使用 in 判斷會存在問題:
class A(object): @property def prop(self): return 3 a = A() print ""prop" in a.__dict__ =", "prop" in a.__dict__ print "hasattr(a, "prop") =", hasattr(a, "prop") print "a.prop =", a.prop # "prop" in a.__dict__ = False # hasattr(a, "prop") = True # a.prop = 3
建議使用 hasattr、getattr、setattr 這種方式對于對象屬性進行操作:
class Example(object): def __init__(self): self.name = "ex" def printex(self): print "This is an example" # Check object has attributes # hasattr(obj, "attr") ex = Example() hasattr(ex,"name") # True hasattr(ex,"printex") # True hasattr(ex,"print") # False # Get object attribute # getattr(obj, "attr") getattr(ex,"name") # "ex" # Set object attribute # setattr(obj, "attr", value) setattr(ex,"name","example") ex.name # "example"異常與測試 異常處理 Context Manager - with
with 常用于打開或者關閉某些資源:
host = "localhost" port = 5566 with Socket(host, port) as s: while True: conn, addr = s.accept() msg = conn.recv(1024) print msg conn.send(msg) conn.close()單元測試
from __future__ import print_function import unittest def fib(n): return 1 if n<=2 else fib(n-1)+fib(n-2) def setUpModule(): print("setup module") def tearDownModule(): print("teardown module") class TestFib(unittest.TestCase): def setUp(self): print("setUp") self.n = 10 def tearDown(self): print("tearDown") del self.n @classmethod def setUpClass(cls): print("setUpClass") @classmethod def tearDownClass(cls): print("tearDownClass") def test_fib_assert_equal(self): self.assertEqual(fib(self.n), 55) def test_fib_assert_true(self): self.assertTrue(fib(self.n) == 55) if __name__ == "__main__": unittest.main()存儲 文件讀寫 路徑處理
Python 內置的 __file__ 關鍵字會指向當前文件的相對路徑,可以根據它來構造絕對路徑,或者索引其他文件:
# 獲取當前文件的相對目錄 dir = os.path.dirname(__file__) # srcapp ## once you"re at the directory level you want, with the desired directory as the final path node: dirname1 = os.path.basename(dir) dirname2 = os.path.split(dir)[1] ## if you look at the documentation, this is exactly what os.path.basename does. # 獲取當前代碼文件的絕對路徑,abspath 會自動根據相對路徑與當前工作空間進行路徑補全 os.path.abspath(os.path.dirname(__file__)) # D:WorkSpaceOWS oolui-tool-svnpythonsrcapp # 獲取當前文件的真實路徑 os.path.dirname(os.path.realpath(__file__)) # D:WorkSpaceOWS oolui-tool-svnpythonsrcapp # 獲取當前執行路徑 os.getcwd()
可以使用 listdir、walk、glob 模塊來進行文件枚舉與檢索:
# 僅列舉所有的文件 from os import listdir from os.path import isfile, join onlyfiles = [f for f in listdir(mypath) if isfile(join(mypath, f))] # 使用 walk 遞歸搜索 from os import walk f = [] for (dirpath, dirnames, filenames) in walk(mypath): f.extend(filenames) break # 使用 glob 進行復雜模式匹配 import glob print(glob.glob("/home/adam/*.txt")) # ["/home/adam/file1.txt", "/home/adam/file2.txt", .... ]簡單文件讀寫
# 可以根據文件是否存在選擇寫入模式 mode = "a" if os.path.exists(writepath) else "w" # 使用 with 方法能夠自動處理異常 with open("file.dat",mode) as f: f.write(...) ... # 操作完畢之后記得關閉文件 f.close() # 讀取文件內容 message = f.read()復雜格式文件 JSON
import json # Writing JSON data with open("data.json", "w") as f: json.dump(data, f) # Reading data back with open("data.json", "r") as f: data = json.load(f)XML
我們可以使用 lxml 來解析與處理 XML 文件,本部分即對其常用操作進行介紹。lxml 支持從字符串或者文件中創建 Element 對象:
from lxml import etree # 可以從字符串開始構造 xml = "" root = etree.fromstring(xml) etree.tostring(root) # b"" # 也可以從某個文件開始構造 tree = etree.parse("doc/test.xml") # 或者指定某個 baseURL root = etree.fromstring(xml, base_url="http://where.it/is/from.xml")
其提供了迭代器以對所有元素進行遍歷:
# 遍歷所有的節點 for tag in tree.iter(): if not len(tag): print tag.keys() # 獲取所有自定義屬性 print (tag.tag, tag.text) # text 即文本子元素值 # 獲取 XPath for e in root.iter(): print tree.getpath(e)
lxml 支持以 XPath 查找元素,不過需要注意的是,XPath 查找的結果是數組,并且在包含命名空間的情況下,需要指定命名空間:
root.xpath("http://page/text/text()",ns={prefix:url}) # 可以使用 getparent 遞歸查找父元素 el.getparent()
lxml 提供了 insert、append 等方法進行元素操作:
# append 方法默認追加到尾部 st = etree.Element("state", name="New Mexico") co = etree.Element("county", name="Socorro") st.append(co) # insert 方法可以指定位置 node.insert(0, newKid)Excel
可以使用 [xlrd]() 來讀取 Excel 文件,使用 xlsxwriter 來寫入與操作 Excel 文件。
# 讀取某個 Cell 的原始值 sh.cell(rx, col).value
# 創建新的文件 workbook = xlsxwriter.Workbook(outputFile) worksheet = workbook.add_worksheet() # 設置從第 0 行開始寫入 row = 0 # 遍歷二維數組,并且將其寫入到 Excel 中 for rowData in array: for col, data in enumerate(rowData): worksheet.write(row, col, data) row = row + 1 workbook.close()文件系統
對于高級的文件操作,我們可以使用 Python 內置的 shutil
# 遞歸刪除 appName 下面的所有的文件夾 shutil.rmtree(appName)網絡交互 Requests
Requests 是優雅而易用的 Python 網絡請求庫:
import requests r = requests.get("https://api.github.com/events") r = requests.get("https://api.github.com/user", auth=("user", "pass")) r.status_code # 200 r.headers["content-type"] # "application/json; charset=utf8" r.encoding # "utf-8" r.text # u"{"type":"User"..." r.json() # {u"private_gists": 419, u"total_private_repos": 77, ...} r = requests.put("http://httpbin.org/put", data = {"key":"value"}) r = requests.delete("http://httpbin.org/delete") r = requests.head("http://httpbin.org/get") r = requests.options("http://httpbin.org/get")數據存儲 MySQL
import pymysql.cursors # Connect to the database connection = pymysql.connect(host="localhost", user="user", password="passwd", db="db", charset="utf8mb4", cursorclass=pymysql.cursors.DictCursor) try: with connection.cursor() as cursor: # Create a new record sql = "INSERT INTO `users` (`email`, `password`) VALUES (%s, %s)" cursor.execute(sql, ("webmaster@python.org", "very-secret")) # connection is not autocommit by default. So you must commit to save # your changes. connection.commit() with connection.cursor() as cursor: # Read a single record sql = "SELECT `id`, `password` FROM `users` WHERE `email`=%s" cursor.execute(sql, ("webmaster@python.org",)) result = cursor.fetchone() print(result) finally: connection.close()
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