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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def pad_array(in1):
 """ Simple convenience function to pad arrays for linear convolution. INPUTS: in1 (no default):
 Input array which is to be padded. OUTPUTS: out1 Padded version of the input. """


    padded_size = 2*np.array(in1.shape)

    out1 = np.zeros([padded_size[0],padded_size[1]])
    out1[padded_size[0]/4:3*padded_size[0]/4,padded_size[1]/4:3*padded_size[1]/4] = in1

    return out1