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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 build_edit_form(title, id, cols, return_page):
 """ returns the html for a simple edit form """

    txt = '<H3>' + title + '<H3>'
    txt += '<form action="' + return_page + '" method="POST">\n' # return_page = /agents
    txt += '  updating id:' + str(id) + '\n<BR>'
    txt += '  <input type="hidden" name="rec_id" readonly value="' + str(id) + '"> '
    txt += '  <TABLE width=80% valign=top border=1>'
    
    for col_num, col in enumerate(cols):
        txt += '  <TR>\n'
        txt += '    <TD><div id="form_label">' + col + '</div></TD>\n'
        txt += '    <TD><div id="form_input"><input type="text" name="col_' + str(col_num) + '"></div></TD>\n'
        txt += '  </TR>\n'
    txt += '  <TR><TD></TD>\n'
    txt += '  <TD>\n'
    txt += '    <input type="submit" name="update-form" value="Save Changes">\n'
    txt += '    <input type="submit" name="delete-form" value="Delete">\n'
    txt += '    <input type="submit" name="add-form" value="Add">\n'
    txt += '  </TD></TR></TABLE>'
    txt += '</form>\n'
    return txt