20240416 falsy conditional
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# falsy conditional
value = (False or [] or None or ''or () \
or {} or 0 )
"""whats is the last value?"""
print(value)
value = (1 and [1]and (1,2) and 1.0 and [1,2])
print(value)
a=5
value = (a ==5 and a <10)
""" a.__lt__(10) 等於a <10) a.__gt__(10) """
print(value)
default_city ="kw"
city='hk'
city = city or print("please input city") \
or default_city
print(city)
city=''
city = bool(city) or print("please input city") \
or default_city
print(city)
#https://pythongeeks.org/python-operator-precedence/
#LIST 折開兩件
print("LIST 折開兩件")
a = [1,2,3,4,5,6]
b = a[0]
c = a[1::]
d,*e,f=a
str_list =[str(numABC) for numABC in a]
g=[*str_list]
print(d)
print(e) #the rest elements group into as list
print(f)
print(g)
#合并成一个新列表
print("合并成一个新列表")
l1 =[1,2,3]
l2 =[4,5,6]
l=[*l1,*l2]
print(l)
l1 =[1,2,3]
l2 ='x,y,z'
l=[*l1,*l2]
print(l)
print("mark six 1-49")
six= {i for i in range(1,50)}
print(six)
#如果用SET 會RANDON 因為不會排
print("如果用SET 會RANDON 因為不會排")
s={10,-99,3,'d'}
print(s)
s={10,-99,3,'d'}
a, *b, c =s
print(a)
print(b)
print(c)
print("*應用")
d1= {'p':1,'y':2}
d2= {'t':3,'h':4}
d3= {'h':5,'o':6,'n':7}
l = [*d1,*d2,*d3]
s = {*d1,*d2,*d3}
print(l)
print(s)
print("**應用")
d1= {'p':1,'y':2}
d2= {'t':3,'h':4}
d3= {'h':5,'o':6,'n':7}
ee={**d1,**d2,**d3}
print(ee)
dd={"p":1,"y":2,"t":3,"h":4}
a,*b=dd
print("dd")
print(dd)
di ={"name":"john","age":30}
ali =[*di]
li =[value for key,value in di.items()]
ii =[key for key,value in di.items()]
lli = di.values()
print("lli",lli)
print(ali)
print(ii)
print(li)
print("function 無處不在")
def a():
print("i am from function a")
b={"name":"john","age":a}
b["age"]()
print("function 內套function 無處不在2")
print("###lambdaba 用途###")
x = lambda a: a + 10
print(x(5))
print("###lambdaba 用途###")
def a():
print("i am from function a")
def d(e):
e()
b={"name":"john","age":lambda : print("i am from BBB")}
b["age"]()
c={"addres":"main street","age":b["age"]}
c["age"]()
d(a)
d(c["age"])
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