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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 step_definition(step_name):
 """ Get the source of a step function. Returned object has keys "filename", "lineno", "text" and "html". "text" is the raw text of the function, "html" has been marked up by Pygments. """

    if not orca.is_step(step_name):
        abort(404)

    filename, lineno, source = \
        orca.get_step(step_name).func_source_data()
    html = highlight(source, PythonLexer(), HtmlFormatter())
    return jsonify(filename=filename, lineno=lineno, text=source, html=html)