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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 find_by_content_type(content_type):
 """ Find and return a format by content type. :param content_type: A string describing the internet media type of the format. """

    for format in FORMATS:
        if content_type in format.content_types:
            return format

    raise UnknownFormat('No format found with content type "%s"' % content_type)