nia orig | Python Fiddle

def gen_plate_layout(cols):
    
  pp=[]

for col in range(1, cols + 1):
    for row in ['A', 'B', 'C', 'D', 'E', 'F', 'G', 'H']:
      pp.append(row + str(col))
   
  return pp

set_list = gen_plate_layout(12)

your_list = ['b1', 'b2', 'b3', 'h3', 'a4', 'b4', 'c4', 'd4', 'e4', 'f4', 'g4', 'h4', 'a5', 'b5', 'c5']
your_list = [i.upper() for i in your_list]

#seq2: Deepwell_Mix Destination
list_index = range(len(your_list)) 
deepwell_mx_dest = []
for i in list_index: 
    deepwell_mx_dest.append(set_list[i])

#seq3: miRNA Template Source
set_index = []
plate1 = []
plate2 = []
plate3 = []
cDNA = []
cDNA.append(plate1) 
cDNA.append(plate2) 
cDNA.append(plate3)

for i in list_index: 
    set_index.append(set_list.index(your_list[i]))

print set_index

for i in set_index:
    w = i % 8 + 48 * (i >= 8)
    #print i, w
    if 0 <= i < 16 and i < 8: 
        for x in range(1,7):
            #print w
            plate1.append((set_list[w]))        
            w = w + 8
    elif 0 <= i < 16 and i >= 8:
        for x in range(1,7):
            #print w
            plate1.append((set_list[w]))        
            w = w + 8
    
    elif 16 <= i < 31 and i % 2 == 0:
        for x in set_index:
            x = (x-16) + 8 
            plate2.append((set_list[x]))    
    
    elif 16 <= i < 31 and i % 2 != 0:
        for x in set_index:
            x = (x -16) + 8 
            plate2.append((set_list[x]))  
        
    elif 32 <= i < 47 and i % 2 == 0: 
        for x in set_index:
            x = (x -32) + 8 
            plate3.append((set_list[x]))     
    
    elif 32 <= i < 47 and i % 2 != 0:
       for x in set_index:
            x = (x -32) + 8 
            plate3.append((set_list[x]))              
    else:
            break
    print i, plate1, plate2, plate3
print plate3

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