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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 merge_Fm(dfs_data):
 """Merges Fm-1 and Fm, as defined on page 19 of the paper."""

    FG = dfs_data['FG']
    m = FG['m']
    FGm = FG[m]
    FGm1 = FG[m-1]

    if FGm[0]['u'] < FGm1[0]['u']:
        FGm1[0]['u'] = FGm[0]['u']

    if FGm[0]['v'] > FGm1[0]['v']:
        FGm1[0]['v'] = FGm[0]['v']

    if FGm[1]['x'] < FGm1[1]['x']:
        FGm1[1]['x'] = FGm[1]['x']

    if FGm[1]['y'] > FGm1[1]['y']:
        FGm1[1]['y'] = FGm[1]['y']

    del FG[m]
    FG['m'] -= 1