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! 8: Files) (Guy)</title>
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! 26: <h2>Session Four: XML Handler (Simple tags, Globals, Multiple Targets, Style
! 27: Files) (Guy)</h2>
! 28: <h3><a name="_Toc421867121">XML Files</a></h3>
! 29: <p><span style='color:black'>All HTML / XML files are run through the lonxml
! 30: handler before being served to a user. This allows us to rewrite many portion
! 31: of a document and to support serverside tags. There are 2 ways to add new
! 32: tags to the xml parsing engine, either through LON-CAPA style files or by
! 33: writing Perl tag handlers for the desired tags. </span></p>
! 34: <p><span style='color:black'><b>Global Variables</b></span></p>
! 35: <p><span style='color:black'>*
! 36: <i>$Apache::lonxml::debug</i></span><span
! 37: style='color:black'> - debugging control </span></p>
! 38: <p><span style='color:black'>*
! 39: <i>@Apache::lonxml::pwd</i></span><span
! 40: style='color:black'> - path to the directory containing the file currently being
! 41: processed </span></p>
! 42: <p><span style='color:black'>*
! 43: <i>@Apache::lonxml::outputstack</i></span><span
! 44: style='color:black'> </span></p>
! 45: <p><span style='color:black'><i>$Apache::lonxml::redirection</i></span><span
! 46: style='color:black'> - these two are used for capturing a subset of the output
! 47: for later processing, don't touch them directly use &startredirection
! 48: and &endredirection </span></p>
! 49: <p><span style='color:black'>*
! 50: <i>$Apache::lonxml::import</i></span><span
! 51: style='color:black'> - controls whether the <import> tag actually does anything
! 52: </span></p>
! 53: <p><span style='color:black'>*
! 54: <i>@Apache::lonxml::extlinks</i></span><span
! 55: style='color:black'> - a list of URLs that the user is allowed to look at because
! 56: of the current resource (images, and links) </span></p>
! 57: <p><span style='color:black'>*
! 58: <i>$Apache::lonxml::metamode</i></span><span
! 59: style='color:black'> - some output is turned off, the meta target wants a specific
! 60: subset, use <output> to guarentee that the catianed data will be in
! 61: the parsing output </span></p>
! 62: <p><span style='color:black'>*
! 63: <i>$Apache::lonxml::evaluate</i></span><span
! 64: style='color:black'> - controls whether run::evaluate actually derefences variable
! 65: references </span></p>
! 66: <p><span style='color:black'>*
! 67: <i>%Apache::lonxml::insertlist</i></span><span
! 68: style='color:black'> - data structure for edit mode, determines what tags can
! 69: go into what other tags </span></p>
! 70: <p><span style='color:black'>*
! 71: <i>@Apache::lonxml::namespace</i></span><span
! 72: style='color:black'> - stores the list of tag namespaces used in the insertlist.tab
! 73: file that are currently active, used only in edit mode. </span></p>
! 74: <p><span style='color:black'>*
! 75: <i>$Apache::lonxml::registered</i></span><span
! 76: style='color:black'> - set to 1 once the remote has been updated to know what
! 77: resource we are looking at. </span></p>
! 78: <p><span style='color:black'>*
! 79: <i>$Apache::lonxml::request</i></span><span
! 80: style='color:black'> - current Apache request object, or undef </span></p>
! 81: <p><span style='color:black'>*
! 82: <i>$Apache::lonxml::curdepth</i></span><span
! 83: style='color:black'> - current depth of the overall parse depth. Will be a string
! 84: like: 2_3_1 (first tag in the third second level tag in the second toplevel
! 85: tag). It gets set by callsub, and can be used in Perl tag implementations.
! 86: It relies upon the internal globals: <i>@Apache::lonxml::depthcounter</i></span><span
! 87: style='color:black'>, <i>$Apache::lonxml::depth</i></span><span
! 88: style='color:black'>, <i>$Apache::lonxml::olddepth</i></span><span
! 89: style='color:black'> </span></p>
! 90: <p><span style='color:black'>*
! 91: <i>$Apache::lonxml::prevent_entity_encode</i></span><span
! 92: style='color:black'> - By default the xmlparser will try to rencode any 8-bit
! 93: characters into HTMLEntity Codes, If this is set to a true value it will be
! 94: prevented. </span></p>
! 95: <p><span style='color:black'>In common usage, <i>$Apache::lonxml::prevent_entity_encode</i></span><span
! 96: style='color:black'>, <i>$Apache::lonxml::evaluate</i></span><span
! 97: style='color:black'>, <i>$Apache::lonxml::metamode</i></span><span
! 98: style='color:black'>, <i>$Apache::lonxml::import</i></span><span
! 99: style='color:black'>, should never be set to a value directly, but rather incremented
! 100: when you want the effect on, and decremented when you want the effect off.
! 101: </span></p>
! 102: <p><span style='color:black'><b>Notable Perl subroutines</b></span></p>
! 103: <p><span style='color:black'>If not specified these functions are in Apache::lonxml
! 104: </span></p>
! 105: <p><span style='color:black'>*
! 106: <i>xmlparse</i></span><span
! 107: style='color:black'> - see the XMLPARSE figure - also not callable from inside
! 108: a tag, if one needs to restart parsing, either create add a new LCParser to
! 109: the parser stack parser using the newparser function, or call inner_xmlparser,
! 110: see the xmlparse function in scripttag.pm </span></p>
! 111: <p><span style='color:black'>*
! 112: <i>recurse</i></span><span
! 113: style='color:black'> - acts just like <i>xmlparse</i></span><span
! 114: style='color:black'>, except it doesn't do the style definition check it always
! 115: calls <i>callsub</i></span><span style='color:black'> </span></p>
! 116: <p><span style='color:black'>*
! 117: <i>callsub</i></span><span
! 118: style='color:black'> - callsub looks if a perl subroutine is defined for the current
! 119: tag and calls. Otherwise it just returns the tag as it was read in. It also
! 120: will throw on a default editing interface unless the tag has a defined subroutine
! 121: that either returns something or requests that call sub not add the editing
! 122: interface. </span></p>
! 123: <p><span style='color:black'>*
! 124: <i>afterburn</i></span><span
! 125: style='color:black'> - called on the output of xmlparse, it can add highlights,
! 126: anchors, and links to regular expersion matches to the output. </span></p>
! 127: <p><span style='color:black'>*
! 128: <i>register_insert</i></span><span
! 129: style='color:black'> - builds the %Apache::lonxml::insertlist structure of what
! 130: tags can have what other tags inside. </span></p>
! 131: <p><span style='color:black'>*
! 132: <i>whichuser</i></span><span
! 133: style='color:black'> - returns a list of $symb, $courseid, $domain, $name that
! 134: is correct for calls to lonnet functions for this setup. Uses form.grade_
! 135: parameters, if the user is allowed to mgr in the course </span></p>
! 136: <p><span style='color:black'>*
! 137: <i>setup_globals</i></span><span
! 138: style='color:black'> - initializes all lonxml globals when xmlparse is called.
! 139: If you intend to create a new target you will likely need to tweak how the
! 140: globals are setup upon start up. </span></p>
! 141: <p><span style='color:black'>*
! 142: <i>init_safespace</i></span><span
! 143: style='color:black'> - creates Holes to external functions, creates some global
! 144: variables, and set the permitted operators of the global Safespace intepreter.
! 145: </span></p>
! 146: <p><span style='color:black'><b>Functions Tag Handlers can use</b></span></p>
! 147: <p><span style='color:black'>If not specified these functions are in Apache::lonxml
! 148: </span></p>
! 149: <p><span style='color:black'>*
! 150: <i>debug</i></span><span
! 151: style='color:black'> - a function to call to printout debugging messages. Will
! 152: only print when Apache::lonxml::debug is set to 1 </span></p>
! 153: <p><span style='color:black'>*
! 154: <i>warning</i></span><span
! 155: style='color:black'> - a function to use for warning messages. The message will
! 156: appear at the top of a resource when it is viewed in construction space only.
! 157: </span></p>
! 158: <p><span style='color:black'>*
! 159: <i>error</i></span><span
! 160: style='color:black'> - a function to use for error messages. The message will
! 161: appear at the top of a resource when it is viewed in construction space, and
! 162: will message the resource author and course instructor, while informing the
! 163: student that an error has occured otherwise. </span></p>
! 164: <p><span style='color:black'>*
! 165: <i>get_all_text</i></span><span
! 166: style='color:black'> - 2 args, tag to look for (need to use /tag to look for an
! 167: end tag) and a HTML::TokeParser reference, it will repedelyt get text from
! 168: the TokeParser until the requested tag is found. It will return all of the
! 169: document it pulled form the TokeParser. (See Apache::scripttag::start_script
! 170: for an example of usage.) </span></p>
! 171: <p><span style='color:black'>*
! 172: <i>get_param</i></span><span
! 173: style='color:black'> - 4 arguments, first is a scaler sting of the argument needed,
! 174: second is a reference to the parser arguments stack, third is a reference
! 175: to the Safe space, and fourth is an optional "context" value. This
! 176: subroutine allows a tag to get a tag argument, after being interpolated inside
! 177: the Safe space. This should be used if the tag might use a safe space variable
! 178: reference for the tag argument. (See Apache::scripttag::start_script for an
! 179: example.) This version only handles scalar variables. </span></p>
! 180: <p><span style='color:black'>*
! 181: <i>get_param_var</i></span><span
! 182: style='color:black'> - 4 arguments, first is a scaler sting of the argument needed,
! 183: second is a reference to the parser arguments stack, third is a reference
! 184: to the Safe space, and fourth is an optional "context" value. This
! 185: subroutine allows a tag to get a tag argument, after being interpolated inside
! 186: the Safe space. This should be used if the tag might use a safe space variable
! 187: reference for the tag argument. (See Apache::scripttag::start_script for an
! 188: example.) This version can handle list or hash variables properly. </span></p>
! 189: <p><span style='color:black'>*
! 190: <i>description</i></span><span
! 191: style='color:black'> - 1 argument, the token object. This will return the textual
! 192: decription of the current tag from the insertlist.tab file. </span></p>
! 193: <p><span style='color:black'>*
! 194: <i>whichuser</i></span><span
! 195: style='color:black'> - 0 arguments. This will take a look at the current environment
! 196: setting and return the current $symb, $courseid, $udom, $uname. You should
! 197: always use this function if you want to determine who the current user is.
! 198: (Since a instructor might be trying to view a students version of a resource.)
! 199: </span></p>
! 200: <p><span style='color:black'>*
! 201: <i>inner_xmlparse</i></span><span
! 202: style='color:black'> - 6 arguments, the target, an array pointer to the current
! 203: stack of tags, and array pointer to the current stack of tag arguments, an
! 204: array pointer to the current stack of LCParser's, a pointer to the current
! 205: Safe space, a pointer to the hash of current style definitions </span></p>
! 206: <p><span style='color:black'>*
! 207: <i>newparser</i></span><span
! 208: style='color:black'> - 3 args, first is a reference to the parser stack, second
! 209: should be a reference to a string scaler containg the text the newparser should
! 210: run over, third should be a scaler of the directory path the file the parser
! 211: is parsing was in. (See Apache::scripttag::start_import for an example.) </span></p>
! 212: <p><span style='color:black'>*
! 213: <i>register</i></span><span
! 214: style='color:black'> - should be called in a file's BEGIN block. 2 arguments,
! 215: a scaler string, and a list of strings. This allows a file to register what
! 216: tags it handles, and what the namespace of those tags are. Example: </span></p>
! 217: <p><span style='font-family:"Courier New";color:black'>sub BEGIN {</span></p>
! 218: <p><span style='font-family:"Courier New";color:black'> &Apache::lonxml::register('Apache::scripttag',('script','display'));</span></p>
! 219: <p><span style='font-family:"Courier New";color:black'>}</span></p>
! 220: <p><span style='color:black'>Would tell xmlparse that in Apache::scripttag it
! 221: can find handlers for <script> and <display>, if one regsiters
! 222: a tag that was already registered the previous one is remembered and will
! 223: be restored on a deregister. </span></p>
! 224: <p><span style='color:black'>*
! 225: <i>deregister</i></span><span
! 226: style='color:black'> - used to remove a previously registered tag implementation.
! 227: It will restore the previous registration if there was one. </span></p>
! 228: <p><span style='color:black'>*
! 229: <i>startredirection</i></span><span
! 230: style='color:black'> - used when a tag wants to save a portion of the document
! 231: for its end tag to use, but wants the intervening document to be normally
! 232: processed. (See Apache::scripttag::start_window for an example.) </span></p>
! 233: <p><span style='color:black'>*
! 234: <i>endredirection</i></span><span
! 235: style='color:black'> - used to stop preventing xmlparse from hiding output. The
! 236: return value is everthing that xmlparse has processed since the corresponding
! 237: startredirection. (See Apache::scripttag::end_window for an example.) </span></p>
! 238: <p><span style='color:black'>*
! 239: <i>Apache::run::evaluate</i></span><span
! 240: style='color:black'> - 3 args, first a string, second a reference to the Safe
! 241: space, 3 a string to be evaluated before the first arg. This subroutine will
! 242: do variable interpolation and simple function interpolations on the first
! 243: argument. (See Apache::lonxml::inner_xmlparse for an example.) </span></p>
! 244: <p><span style='color:black'>*
! 245: <i>Apache::run::run</i></span><span
! 246: style='color:black'> - 2 args, first a string, second a reference to the Safe
! 247: space. This handles passing the passed string into the Safe space for evaluation
! 248: and then returns the result. (See Apache::scripttag::start_script for an example.)</span></p>
! 249: <h3><a name="_Toc421867122">Style Files</a></h3>
! 250: <p><span style='color:black'> <img width=432 height=255
! 251: src="Session%20Fou1_files/image002.jpg" v:shapes="_x0000_i1025"> </span></p>
! 252: <p><span style='font-size:14.0pt;color:black'><b>Fig. 2.4.1</b></span><span
! 253: style='font-size:14.0pt;color:black'> Ð Using a style file</span></p>
! 254: <p><span style='color:black'><b>Style File specific tags</b></span></p>
! 255: <p><span style='color:black'><b><definetag></b></span><span
! 256: style='color:black'> - 2 arguments, <i>name</i></span><span style='color:black'>
! 257: name of new tag being defined, if proceeded with a / defining an end tag,
! 258: required; <i>parms</i></span><span style='color:black'> parameters of the
! 259: new tag, the value of these parameters can be accesed by $parametername. </span></p>
! 260: <p><span style='color:black'>*
! 261: <b><render></b></span><span
! 262: style='color:black'> - define what the new tag does for a non meta target </span></p>
! 263: <p><span style='color:black'>*
! 264: <b><meta></b></span><span
! 265: style='color:black'> - define what the new tag does for a meta target </span></p>
! 266: <p><span style='color:black'>*
! 267: <b><tex> / <web> / <latexsource></b></span><span style='color:black'>
! 268: - define what a new tag does for a specific no meta target, all data inside
! 269: a <render> is render to all targets except when surrounded by a specific
! 270: target tags.</span><span style='font-size:16.0pt;color:black'> </span></p>
! 271: <p class=MsoHeader> <img width=432 height=243
! 272: src="Session%20Fou1_files/image005.png" v:shapes="_x0000_i1026"> </p>
! 273: <p><span style='font-size:14.0pt'><b>Fig. 2.4.2</b></span><span
! 274: style='font-size:14.0pt'> Ð The parser</span></p>
! 275: <h3><a name="_Toc421867123">HTML::LCParser - Alternative HTML::Parser interface</a></h3>
! 276: <p class=MsoPlainText>SYNOPSIS</p>
! 277: <p class=MsoPlainText> require HTML::LCParser;</p>
! 278: <p class=MsoPlainText> $p = HTML::LCParser->new("index.html")
! 279: || die "Can't open: $!";</p>
! 280: <p class=MsoPlainText> while (my $token = $p->get_token) {</p>
! 281: <p class=MsoPlainText> #...</p>
! 282: <p class=MsoPlainText> }</p>
! 283: <p class=MsoPlainText>DESCRIPTION</p>
! 284: <p class=MsoPlainText>The C<HTML::LCParser> is an alternative interface
! 285: to the</p>
! 286: <p class=MsoPlainText>C<HTML::Parser> class. It is an C<HTML::PullParser>
! 287: subclass.</p>
! 288: <p class=MsoPlainText>The following methods are available:</p>
! 289: <p class=MsoPlainText>* $p = HTML::LCParser->new( $file_or_doc );</p>
! 290: <p class=MsoPlainText>The object constructor argument is either a file name,
! 291: a file handle</p>
! 292: <p class=MsoPlainText>object, or the complete document to be parsed.</p>
! 293: <p class=MsoPlainText>If the argument is a plain scalar, then it is taken as
! 294: the name of a</p>
! 295: <p class=MsoPlainText>file to be opened and parsed. If the file can't
! 296: be opened for</p>
! 297: <p class=MsoPlainText>reading, then the constructor will return an undefined
! 298: value and $!</p>
! 299: <p class=MsoPlainText>will tell you why it failed.</p>
! 300: <p class=MsoPlainText>If the argument is a reference to a plain scalar, then
! 301: this scalar is</p>
! 302: <p class=MsoPlainText>taken to be the literal document to parse. The value
! 303: of this</p>
! 304: <p class=MsoPlainText>scalar should not be changed before all tokens have been
! 305: extracted.</p>
! 306: <p class=MsoPlainText>Otherwise the argument is taken to be some object that
! 307: the</p>
! 308: <p class=MsoPlainText>C<HTML::LCParser> can read() from when it needs
! 309: more data. Typically</p>
! 310: <p class=MsoPlainText>it will be a filehandle of some kind. The stream
! 311: will be read() until</p>
! 312: <p class=MsoPlainText>EOF, but not closed.</p>
! 313: <p class=MsoPlainText>It also will turn attr_encoded on by default.</p>
! 314: <p class=MsoPlainText>* $p->get_token</p>
! 315: <p class=MsoPlainText>This method will return the next I<token> found
! 316: in the HTML document,</p>
! 317: <p class=MsoPlainText>or C<undef> at the end of the document. The
! 318: token is returned as an</p>
! 319: <p class=MsoPlainText>array reference. The first element of the array
! 320: will be a (mostly)</p>
! 321: <p class=MsoPlainText>single character string denoting the type of this token:
! 322: "S" for start</p>
! 323: <p class=MsoPlainText>tag, "E" for end tag, "T" for text,
! 324: "C" for comment, "D" for</p>
! 325: <p class=MsoPlainText>declaration, and "PI" for process instructions.
! 326: The rest of the array</p>
! 327: <p class=MsoPlainText>is the same as the arguments passed to the corresponding
! 328: HTML::Parser</p>
! 329: <p class=MsoPlainText>v2 compatible callbacks (see L<HTML::Parser>).
! 330: In summary, returned</p>
! 331: <p class=MsoPlainText>tokens look like this:</p>
! 332: <p class=MsoPlainText> ["S", $tag, $attr, $attrseq, $text,
! 333: $line]</p>
! 334: <p class=MsoPlainText> ["E", $tag, $text, $line]</p>
! 335: <p class=MsoPlainText> ["T", $text, $is_data, $line]</p>
! 336: <p class=MsoPlainText> ["C", $text, $line]</p>
! 337: <p class=MsoPlainText> ["D", $text, $line]</p>
! 338: <p class=MsoPlainText> ["PI", $token0, $text, $line]</p>
! 339: <p class=MsoPlainText>where $attr is a hash reference, $attrseq is an array
! 340: reference and</p>
! 341: <p class=MsoPlainText>the rest are plain scalars.</p>
! 342: <p class=MsoPlainText>* $p->unget_token($token,...)</p>
! 343: <p class=MsoPlainText>If you find out you have read too many tokens you can
! 344: push them back,</p>
! 345: <p class=MsoPlainText>so that they are returned the next time $p->get_token
! 346: is called.</p>
! 347: <p class=MsoPlainText>* $p->get_tag( [$tag, ...] )</p>
! 348: <p class=MsoPlainText>This method returns the next start or end tag (skipping
! 349: any other</p>
! 350: <p class=MsoPlainText>tokens), or C<undef> if there are no more tags in
! 351: the document. If</p>
! 352: <p class=MsoPlainText>one or more arguments are given, then we skip tokens until
! 353: one of the</p>
! 354: <p class=MsoPlainText>specified tag types is found. For example:</p>
! 355: <p class=MsoPlainText> $p->get_tag("font", "/font");</p>
! 356: <p class=MsoPlainText>will find the next start or end tag for a font-element.</p>
! 357: <p class=MsoPlainText>The tag information is returned as an array reference
! 358: in the same form</p>
! 359: <p class=MsoPlainText>as for $p->get_token above, but the type code (first
! 360: element) is</p>
! 361: <p class=MsoPlainText>missing. A start tag will be returned like this:</p>
! 362: <p class=MsoPlainText> [$tag, $attr, $attrseq, $text]</p>
! 363: <p class=MsoPlainText>The tagname of end tags are prefixed with "/",
! 364: i.e. end tag is</p>
! 365: <p class=MsoPlainText>returned like this:</p>
! 366: <p class=MsoPlainText> ["/$tag", $text]</p>
! 367: <p class=MsoPlainText>* $p->get_text( [$endtag] )</p>
! 368: <p class=MsoPlainText>This method returns all text found at the current position.
! 369: It will</p>
! 370: <p class=MsoPlainText>return a zero length string if the next token is not text.
! 371: The</p>
! 372: <p class=MsoPlainText>optional $endtag argument specifies that any text occurring
! 373: before the</p>
! 374: <p class=MsoPlainText>given tag is to be returned. All entities are unmodified.</p>
! 375: <p class=MsoPlainText>The $p->{textify} attribute is a hash that defines
! 376: how certain tags can</p>
! 377: <p class=MsoPlainText>be treated as text. If the name of a start tag matches
! 378: a key in this</p>
! 379: <p class=MsoPlainText>hash then this tag is converted to text. The hash
! 380: value is used to</p>
! 381: <p class=MsoPlainText>specify which tag attribute to obtain the text from.
! 382: If this tag</p>
! 383: <p class=MsoPlainText>attribute is missing, then the upper case name of the
! 384: tag enclosed in</p>
! 385: <p class=MsoPlainText>brackets is returned, e.g. "[IMG]". The
! 386: hash value can also be a</p>
! 387: <p class=MsoPlainText>subroutine reference. In this case the routine is
! 388: called with the</p>
! 389: <p class=MsoPlainText>start tag token content as its argument and the return
! 390: value is treated</p>
! 391: <p class=MsoPlainText>as the text.</p>
! 392: <p class=MsoPlainText>The default $p->{textify} value is:</p>
! 393: <p class=MsoPlainText> {img => "alt", applet => "alt"}</p>
! 394: <p class=MsoPlainText>This means that <IMG> and <APPLET> tags are
! 395: treated as text, and that</p>
! 396: <p class=MsoPlainText>the text to substitute can be found in the ALT attribute.</p>
! 397: <p class=MsoPlainText>* $p->get_trimmed_text( [$endtag] )</p>
! 398: <p class=MsoPlainText>Same as $p->get_text above, but will collapse any sequences
! 399: of white</p>
! 400: <p class=MsoPlainText>space to a single space character. Leading and trailing
! 401: white space is</p>
! 402: <p class=MsoPlainText>removed.</p>
! 403: <p class=MsoPlainText>EXAMPLES</p>
! 404: <p class=MsoPlainText>This example extracts all links from a document.
! 405: It will print one</p>
! 406: <p class=MsoPlainText>line for each link, containing the URL and the textual
! 407: description</p>
! 408: <p class=MsoPlainText>between the <A>...</A> tags:</p>
! 409: <p class=MsoPlainText> use HTML::LCParser;</p>
! 410: <p class=MsoPlainText> $p = HTML::LCParser->new(shift||"index.html");</p>
! 411: <p class=MsoPlainText> while (my $token = $p->get_tag("a"))
! 412: {</p>
! 413: <p class=MsoPlainText> my $url = $token->[1]{href}
! 414: || "-";</p>
! 415: <p class=MsoPlainText> my $text = $p->get_trimmed_text("/a");</p>
! 416: <p class=MsoPlainText> print "$url\t$text\n";</p>
! 417: <p class=MsoPlainText> }</p>
! 418: <p class=MsoPlainText>This example extract the <TITLE> from the document:</p>
! 419: <p class=MsoPlainText> use HTML::LCParser;</p>
! 420: <p class=MsoPlainText> $p = HTML::LCParser->new(shift||"index.html");</p>
! 421: <p class=MsoPlainText> if ($p->get_tag("title")) {</p>
! 422: <p class=MsoPlainText> my $title = $p->get_trimmed_text;</p>
! 423: <p class=MsoPlainText> print "Title: $title\n";</p>
! 424: <p class=MsoPlainText> }</p>
! 425: </div>
! 426: <br
! 427: clear=ALL style='page-break-before:always;'>
! 428: <div class=Section2> </div>
! 429: </body>
! 430: </html>
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