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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 global_max(col_vals, index):

 """Returns the global maximum and minimum."""

    col_vals_without_None = [x for x in col_vals if x is not None]
    max_col, min_col = zip(*col_vals_without_None)
    return max(max_col), min(min_col)