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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 _repr_html_(self):
 """Give a nice representation of tables in notebooks."""

        out = "<table class='taqltable' style='overflow-x:auto'>\n"

        # Print column names (not if they are all auto-generated)
        if not(all([colname[:4] == "Col_" for colname in self.colnames()])):
            out += "<tr>"
            for colname in self.colnames():
                out += "<th><b>"+colname+"</b></th>"
            out += "</tr>"

        cropped = False
        rowcount = 0
        for row in self:
            rowout = _format_row(row, self.colnames(), self)
            rowcount += 1
            out += rowout
            if "\n" in rowout:  # Double space after multiline rows
                out += "\n"
            out += "\n"
            if rowcount >= 20:
                cropped = True
                break

        if out[-2:] == "\n\n":
            out = out[:-1]

        out += "</table>"

        if cropped:
            out += ("<p style='text-align:center'>(" +
                    str(self.nrows()-20)+" more rows)</p>\n")

        return out