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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 dict_to_qs(dct):
 """ Takes a dictionary and uses it to create a query string. """

    itms = ["%s=%s" % (key, val) for key, val in list(dct.items())
            if val is not None]
    return "&".join(itms)