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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 from_data(data):
 """ Construct a Prettytable from list of rows. """

    if len(data) == 0:  # pragma: no cover
        return None
    else:
        ptable = PrettyTable()
        ptable.field_names = data[0].keys()
        for row in data:
            ptable.add_row(row)
        return ptable