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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 preview(num):
 """Prints the text of a problem."""

    # Define problem_text before echoing in case problem does not exist
    problem_text = Problem(num).text
    click.secho("Project Euler Problem %i" % num, bold=True)
    click.echo(problem_text)