Key methods for dictionary, string, and list in Python

1. How to merge dictionaries

Despite what Guido says, dict(x, **y) is in line with the dict specification, which works for both Python 2 and 3. The fact that this only works for string keys is a direct consequence of how keyword parameters work, not a shortcoming of dict. However, using the ** operator in this place is not an abuse of the mechanism, in fact, ** was designed precisely to pass dictionaries as keywords.

Combining two dictionaries:

dict(D1, **D2)

Combining multiple dictionaries:

{**D1, **D2, **D3}

Refer to the python code:

D1={"A":1,"B":2}
D2={"C":3,"D":4}
d3={"E":1,"A to E":11}
print("two dict merge")
print(dict(D1, **D2))
print("multiple dictionaries merge")
print({**D1,**D2,**d3})

2. How to use string.join()

" ".join() allows us to concatenate the strings of the same list:

Arr=['hello','learn','python,
'with','FUN']
" ".join(Arr)

Let’s take a look into the Python code:

Arr=['hello','learn','python', "with","fun"]
print("before joining the array:\n",Arr)
k=" ".join(Arr)
print('after joining :\n',k)
#concat with diff spl characters
k1="-".join(Arr)
k2="$".join(Arr)
print( k1,"\n",k2)

3. How to create a list with elements in a specific range

Instead of initializing the elements of a list (as shown below),

 list=[11,12,13,14,145,12,127] 

we can simply use range() in list.

Let’s look at the Python code below:

print("\t Range Into List")
K=list(range(11,20))
print(K)

4. How to extract nested lists

L=[[10],[100],[1000],[10000]]
L1=sum(L,[])
print(L1)
L=[[10],[100],[1000],[10000]]
print("the nested list:",L)
L1=sum(L,[])
print("after extracting it:",L1)