Here is the code to accomplish the objective and tasks:

result = []  # Initialize an empty result array
for i in range(6, 13):  # Loop through rows 6 to 12
    cell_range = f"A{i}:B{i}"  # Concatenate cell range string
    result.append(cell_range)  # Add cell range to result array
output_string = ", ".join(result)  # Join result array into string with comma and space separator

The range function is used to loop through the rows 6 to 12, and the f-string formatting is used to concatenate the cell range string for each row. The resulting cell range strings are added to the result array using the append method. Finally, the join method is used to combine the cell range strings in the result array into a single output string with a comma and space separator.

The output string would be:

"A6:B6, A7:B7, A8:B8, A9:B9, A10:B10, A11:B11, A12:B12"
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