Day --- python tuples and dictionaries of magic

# Tuple elements can not change, add, delete 
the first stage element # tuple can not be modified, deleted, added 
# tuples are generally written, the last comma 
tu = (123, "wdsd" , 213, (213 , 213), [(31 is, "wdsd")], True, 43 is, 67,) 

# index 
V1 = TU [0] 
Print (V1) 

# slice 
V2 = TU [0: 2] 
Print (V2) 


# for loop iteration also can be subject 
# count acquisition times specified element appears in a tuple 
# index tuple specified in the initial and end positions of the number of occurrences 
for I in TU: 
    Print (I) 

# tuples ordered 
v3 = tu [3 ] [0] 
Print (v3) 

# class dictionary dict 
# dictionary value can be any value 
# key addition to the dictionary lists and dictionaries, are 
# unordered dictionary 

# index ways to find the specified element 
# support del delete 

info = { 
    " k1 ":" v1 ", # key of 
    " K2 ":" V2 " 
} 
V4 = info [ 'k2']
Print (V4) 
 
# for loop
for I1 in info.keys (): # traversing key 
    Print (I1) 

for i2 in info.values (): # traversal value 
    Print (i2) 

for i3, I4 in info.items (): # traversing key and value 
    Print (I3, I4) 

# dictionary method 
# 1, clear clear 

# 2, copy shallow copy 

# 3, fromkeys, according to the sequence, to create the dictionary, and assign a uniform value 

v5 = dict.fromkeys ([ "k1" , "K2", "K3"], [123, 433, 456]) 
Print (V5) 

#. 4, according to the key value acquired when the key does not exist, can specify the default value (None) 

V6 = info.get ( "K2 ", 123) 
Print (V6) 

#. 5, and acquires the POP and remove popitem value 

V7 = v5.pop (" K1 ", 30) 
Print (V5, V7) 
V8, V9 = v5.popitem () 
Print (V5, V8 , V9) 

#. 6, setDefault set value is not set exists, acquires a value corresponding to the absence of setting

v10 = info.setdefault("k3", "456")
get, update, keys, values,
five dictionary
print(v10, info)

# 7、update更新

info.update({'k1': '111', 'k4': '444'})
print(info)
info.update(k1=100, k2=200,k5='wu')
print(info)

############################
"""
重要的
keys（）
values（）
items（）
get（）
upadte（）
"""
###################  大整理 ###########
"""
false None, "", (),
0 1
index, slicing cycle (one element can not be deleted , add, modify)
quad
the index, slicing, cyclic
append, extend, insert
three lists
replace, find, join, strip,
two strings
int
A digital


for loop, the index 

six Boolean value 
BOOL () 
"" "
Day --- python tuples and dictionaries of magic

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