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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 paragraph_generator(sentences=None):
 """Creates a generator for generating paragraphs. :arg sentences: list or tuple of sentences you want to use; defaults to LOREM :returns: generator Example:: from eadred.helpers import paragraph_generator gen = paragraph_generator() for i in range(50):
 mymodel = SomeModel(description=gen.next()) mymodel.save() """

    if sentences is None:
        sentences = LOREM

    while True:
        # Paragraph consists of 1-7 sentences.
        paragraph = [random.choice(sentences)
                     for num in range(random.randint(1, 7))]
        yield u' '.join(paragraph)