how to take matrix input in python

1# A basic code for matrix input from user 
2  
3R = int(input("Enter the number of rows:")) 
4C = int(input("Enter the number of columns:")) 
5  
6# Initialize matrix 
7matrix = [] 
8print("Enter the entries rowwise:") 
9  
10# For user input 
11for i in range(R):          # A for loop for row entries 
12    a =[] 
13    for j in range(C):      # A for loop for column entries 
14         a.append(int(input())) 
15    matrix.append(a) 
16  
17# For printing the matrix 
18for i in range(R): 
19    for j in range(C): 
20        print(matrix[i][j], end = " ") 
21    print() 

1If you want to take n lines of input where each line contains m space separated integers like:
2
31 2 3
44 5 6 
57 8 9 
6
7a=[] // declaration 
8for i in range(0,n):   //where n is the no. of lines you want 
9 a.append([int(j) for j in input().split()])  // for taking m space separated integers as input

1matrix = [input().split() for i in range(no_of_rows)] # if only row is given and the number of coloumn has to be decide by user
2matrix= [[input() for j in range(no_of_cols)] for i in range(no_of_rows)] # if both row and coloumn has been taken as input from user

1# Taking one row at a time with space-separated values.
2# And converting each of them to using map and int function.
3
4matrix = []
5for i in range(row):
6   col = list(map(int, input().split()))
7   matrix.append(col)
8print(matrix)
9
10'''
11Input :
121 2
133 4
14Output :
15[[1, 2], [3, 4]]
16'''

1row=int(input("Enter number of rows you want: "))
2col=int(input("Enter number of columns you want: "))
3mat=[]
4for m in range(row):
5  a=[]
6  for n in range(col):
7     a.append(0)
8  mat.append(a)
9
10for i in range(len(mat)):
11  for j in range(len(mat[0])):
12    mat[i][j]=int(input("Input element: "))
13print("Your Matrix is :",mat)