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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 get_pairtree_prefix(pairtree_store):
 """Returns the prefix given in pairtree_prefix file."""

    prefix_path = os.path.join(pairtree_store, 'pairtree_prefix')
    with open(prefix_path, 'r') as prefixf:
        prefix = prefixf.read().strip()
    return prefix