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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 csp_header(csp={}):
 """ Decorator to include csp header on app.route wrapper """

    _csp = csp_default().read()
    _csp.update(csp)
    
    _header = ''
    if 'report-only' in _csp and _csp['report-only'] is True:
    	_header = 'Content-Security-Policy-Report-Only'
    else:
    	_header = 'Content-Security-Policy'
    if 'report-only' in _csp:
    	del _csp['report-only']
    _headers = {_header: create_csp_header(_csp)}
    
    def decorator(f):
        @wraps(f)
        def decorated_function(*args, **kwargs):
            resp = make_response(f(*args, **kwargs))
            h = resp.headers
            for header, value in _headers.items():
                h[header] = value
            return resp
        return decorated_function
    return decorator