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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 dump(context=os.environ):
 """Dump current environment as a dictionary Arguments: context (dict, optional):
 Current context, defaults to the current environment. """


    output = {}
    for key, value in context.iteritems():
        if not key.startswith("BE_"):
            continue
        output[key[3:].lower()] = value

    return output