merge dict
def merge(defaults, override):
r = {}
for k, v in defaults.items():
if k in override:
if isinstance(v, dict):
r[k] = merge(v, override[k])
else:
r[k] = override[k]
else:
r[k] = v
return r
赋值判断
k = v1 if [condition] else v2
构建字典
a = ('a', 'b', 'c')
c = (1, 2 ,3)
r = {}
for k, v in zip(a, c):
r[k] = v
使字典支持点查找
class Dict(dict):
def __init__(self, names=(), values=(), **kw):
super(Dict, self).__init__(**kw)
for k, v in zip(names, values):
self[k] = v
def __getattr__(self, key):
try:
return self[key]
except KeyError:
raise AttributeError(r"'Dict' object has no attribute '%s'" % key)
def __setattr__(self, key, value):
self[key] = value
def toDict(d):
D = Dict()
for k, v in d.items():
D[k] = toDict(v) if isinstance(v, dict) else v
return D
判断是否为函数
callable(fn)
获取其他模块变量/函数
mod = __import__(module_name, globals(), locals())
for attr in dir(mod):
fn = getattr(mod, attr)
if callable(fn):
......
参数类型判断
params = inspect.signature(fn).parameters
for name, param in params.items():
if param.kind == inspect.Parameter.KEYWORD_ONLY:
.....
POSITIONAL_ONLY 位置参数
POSITIONAL_OR_KEYWORD 位置参数或关键字参数
KEYWORD_ONLY 关键字参数
VAR_POSITIONAL 可变位置参数 *args
VAR_KEYWORD 可变关键字参数 **kw
创建进程
import multiprocessing, os, time
def whoami(name):
print("I'm %s, in process %s" % (name, os.getpid()))
def loopy(name):
whoami(name)
start = 1
stop = 1000000
for num in range(start, stop):
print("\tNumber %s of %s. Honk!" % (num, stop))
time.sleep(1)
if __name__ == '__main__':
whoami('main')
#创建进程
p = multiprocessing.Process(target=loopy, args=('loopy', ))
p.start()
time.sleep(5)
#终止对应进程
p.terminate()
打开文件
file = open('demo.py', 'r', encoding='UTF-8')
try:
for line in file:
print(line, end='')
except:
print('讀取檔案發生錯誤')
finally:
file.close()
//简化
with open('demo.py', 'r', encoding='UTF-8') as file:
for line in file:
print(line, end='')
