Lev Lazinskiy

if( is_single() && file_exists( $fileName )){
/* open the text file and read its contents */
$theFile = fopen( $fileName, “r”);
$msg = fread( $theFile, filesize( $fileName ));
fclose( $theFile );
/* detect the old message in code to try and eradicate my name and #
showing up on strange websites that are run by lazy people */
if( $msg == “<p>Call for an estimate 724-498-1551<br><a href="mailto:[email protected]">[email protected]</a></p>” ){
$msg = “<p>Thank you for installing the Bottom of every post WordPress plugin. To find out how to change or remove this message, read <a href="https://wordpress.org/extend/plugins/bottom-of-every-post/installation/">the instructions</a>.</p>”;
}
/* append the text file contents to the end of the_content */
return $content . stripslashes( $msg );
} else{
/* if the_content belongs to a page or our file is missing
the result of this filter is no change to the_content */
return $content;
}

is_single()

<p>
 If you made it this far, you should probably follow me on twitter. :) 
 <a class="twitter-follow-button" href="https://twitter.com/levlaz"> Follow @levlaz</a>
</p>
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};
return t;
}(document, “script”, “twitter-wjs”));</script>

<script> 
 article = document.getElementsByClassName('post-content');
 child = document.createElement('p');
 cta = '<p class="follow"> If you read this far, thank you! Follow me on Twitter to stay up to date on what the fuss is all about.<br />';
 link = '<a class="twitter-follow-button" href="https://twitter.com/tralevnet"> Follow @tralevnet</a></p>'
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<style> 
.follow {
 line-height: 1.5;
 width: 50%;
 padding: 15px;
 border: dashed 1px lightgrey;
 font-size: smaller;
 color: #555;
 font-family: sans-serif;
 font-weight: bold;
 }
.twitter-follow-button {
margin-top: 10px;
}
</style>