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Convert x same size 2D numpy arrays to a 2+x column data frame

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I have two ndarrays of size (m x n), and two lists of length m and n respectively. I want to convert the two matrices to a dataframe with four columns. The first two columns correspond to the m and n dimensions, and contain the values from the lists. The next two columns should contain the values from the two matrices. In total, the resulting dataframe should have m times n rows.