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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 prefix(prefix):
 """Returns a dictionary of all environment variables starting with the given prefix, lower cased and stripped. """


    d = {}
    e = lower_dict(environ.copy())

    prefix = prefix.lower()

    for k, v in e.items():
        try:
            if k.startswith(prefix):
                k = k[len(prefix):]
                d[k] = v
        except AttributeError:
            pass

    return d