值得一提的是，如果您需要将函数（或类）名称和应用程序名称作为字符串传递，那么可以这样做：

myFnName  = "MyFn"
myAppName = "MyApp"
app = sys.modules[myAppName]
fn  = getattr(app,myFnName)

只是一个简单的贡献。如果我们需要实例化的类在同一个文件中，我们可以使用类似的方法：

# Get class from globals and create an instance
m = globals()['our_class']()

# Get the function (from the instance) that we need to call
func = getattr(m, 'function_name')

# Call it
func()

例如：

class A:
    def __init__(self):
        pass

    def sampleFunc(self, arg):
        print('you called sampleFunc({})'.format(arg))

m = globals()['A']()
func = getattr(m, 'sampleFunc')
func('sample arg')

# Sample, all on one line
getattr(globals()['A'](), 'sampleFunc')('sample arg')

如果不是类：

def sampleFunc(arg):
    print('you called sampleFunc({})'.format(arg))

globals()['sampleFunc']('sample arg')

这是一个简单的答案，例如，这将允许您清除屏幕。下面有两个示例，分别是eval和exec，它们将在清理后在顶部打印0（如果您使用的是Windows，请将clear更改为cls，例如，Linux和Mac用户保持原样）或仅执行它。

eval("os.system(\"clear\")")
exec("os.system(\"clear\")")

答案（我希望）从来没有人想要

Eval样行为

getattr(locals().get("foo") or globals().get("foo"), "bar")()

为什么不添加自动导入

getattr(
    locals().get("foo") or 
    globals().get("foo") or
    __import__("foo"), 
"bar")()

万一我们有多余的字典要查

getattr(next((x for x in (f("foo") for f in 
                          [locals().get, globals().get, 
                           self.__dict__.get, __import__]) 
              if x)),
"bar")()

我们需要更深入

getattr(next((x for x in (f("foo") for f in 
              ([locals().get, globals().get, self.__dict__.get] +
               [d.get for d in (list(dd.values()) for dd in 
                                [locals(),globals(),self.__dict__]
                                if isinstance(dd,dict))
                if isinstance(d,dict)] + 
               [__import__])) 
        if x)),
"bar")()

给定一个字符串和一个函数的完整python路径，这就是我如何获得所述函数的结果：

import importlib
function_string = 'mypackage.mymodule.myfunc'
mod_name, func_name = function_string.rsplit('.',1)
mod = importlib.import_module(mod_name)
func = getattr(mod, func_name)
result = func()

虽然getattr（）是一种优雅的（大约快7倍）方法，但您可以使用eval从函数（local、class方法、模块）获得返回值，其优雅程度与x=eval（'fo.bar'）（）相同。当您实现一些错误处理时，就会非常安全（getattr也可以使用相同的原理）。模块导入和类示例：

# import module, call module function, pass parameters and print retured value with eval():
import random
bar = 'random.randint'
randint = eval(bar)(0,100)
print(randint) # will print random int from <0;100)

# also class method returning (or not) value(s) can be used with eval: 
class Say:
    def say(something='nothing'):
        return something

bar = 'Say.say'
print(eval(bar)('nice to meet you too')) # will print 'nice to meet you' 

当模块或类不存在（键入错误或其他更好的错误）时，就会引发NameError。如果函数不存在，则引发AttributeError。这可用于处理错误：

# try/except block can be used to catch both errors
try:
    eval('Say.talk')() # raises AttributeError because function does not exist
    eval('Says.say')() # raises NameError because the class does not exist
    # or the same with getattr:
    getattr(Say, 'talk')() # raises AttributeError
    getattr(Says, 'say')() # raises NameError
except AttributeError:
    # do domething or just...
    print('Function does not exist')
except NameError:
    # do domething or just...
    print('Module does not exist')