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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 is_requirement(line):
 """ Return True if the requirement line is a package requirement; that is, it is not blank, a comment, a URL, or an included file. """

    return not (
        line == '' or
        line.startswith('-r') or
        line.startswith('#') or
        line.startswith('-e') or
        line.startswith('git+')
    )