def dot_product(A, B):
    """
    Returns `dot_product` from a pair of matrix wherein `A` is transposed
    into a row vector and `B` is a column vector.

    Parameters
    ----------
    A : list
        The given left-hand side transposed matrix.
    B : list
        The given right-hand side matrix.

    Returns
    -------
    dot_product : float (scalar)
        dot product of two vectors.

    """
    A_rows = len(A)
    A_columns = len(A[0])

    B_rows = len(B)
    B_columns = len(B[0])

    if (A_columns == B_rows) and (A_rows == 1 and B_columns == 1):

        dot_product = []
        
        for i in range(A_columns):
            dot_product.append(A[0][i]*B[i][0])

        return sum(dot_product)
        
    else:
        print("dimensions of vector do not match.")