Python - Creating Dynamic Matrices

matrices_init.py

def createMatrix():
  _matrix = []

  ms=int(input("Enter no. of matrices to create: "))

  for i in range(ms):
    print("\nMatrix %i"%(i+1))
    r=int(input("\tEnter no. of rows: "))
    c=int(input("\tEnter no. of columns: "))

    m=[]
    b=[]

    for i in range(r):
      for j in range(c):
        v= int(input("\tEnter value for row "+str(i)+" column "+str(j)+": "))
        b.append(v)
      m.append(b)
      b=[]
    
    _matrix.append(m)

  return _matrix

matrix = createMatrix()

# Sample 2 Matrices assigning to m1 & m2
m1 = matrix[0]
m2 = matrix[1]