# 1.判断函数类型
使用hasattr，
hasattr(add, '__call__'),function和可调用的类函数类型都包含__call__属性，可以使用hasattr和callable判断对象是否支持调用，返回为true的对象，不一定是函数。使用isinstance，
isinstance(add, types.FunctionType)，types.FunctionType判断是否是用户定义的函数类型，此外还可以使用types.LambdaType。types中判断内建函数使用types.BuiltinFunctionType,判断是否是类种的方法使用types.MethodType。更多的介绍可以参考doc (opens new window)使用inspect.isfunction，
inspect.isfunction(add),判断一个对象是否是Python种用户自定义的函数，支持判断lambda表达式，但不能够判断built-in类型的函数。inspect是Python中的标准模块，用来检视活动对象，判断对象类型，源文件，源码，检查解释器堆栈等，具体可参考官方文档 (opens new window)。使用callable，
callable(add),callable是Python中的内置函数，判断一个对象是否可调用，类可调用返回一个实例，实例可调用，如果其中定义了__call__方法。
# 2.示例
import types
import inspect
def add(x, y):
print(x+y)
class Model:
def __call__(x, y):
print(f"Model({x}, {y}) is: {x + y}")
print("function add:")
print("isinstance(function): ", isinstance(add, types.FunctionType))
print("isinstance(lambda): ", isinstance(add, types.LambdaType))
print("inspect: ", inspect.isfunction(add))
print("callable: ", callable(add))
print("__call__: ", hasattr(add, '__call__'))
print("Callable Model:")
print("isinstance: ", isinstance(Model, types.FunctionType))
print("inspect: ", inspect.isfunction(Model))
print("callable: ", callable(Model))
print("__call__: ", hasattr(Model, '__call__'))
print("buildin print:")
print("isinstance: ", isinstance(print, types.FunctionType))
print("inspect: ", inspect.isfunction(print))
print("callable: ", callable(print))
print("__call__: ", hasattr(print, '__call__'))
print("BuiltinFunctionType:", isinstance(abs, types.BuiltinFunctionType))
# function add:
# isinstance(function): True
# isinstance(lambda): True
# inspect: True
# callable: True
# __call__: True
# Callable Model:
# isinstance: False
# inspect: False
# callable: True
# __call__: True
# buildin print:
# isinstance: False
# inspect: False
# callable: True
# __call__: True
# BuiltinFunctionType: True