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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 json(a):
 """ Output the json encoding of its argument. This will escape all the HTML/XML special characters with their unicode escapes, so it is safe to be output anywhere except for inside a tag attribute. If the output needs to be put in an attribute, entitize the output of this filter. """

    json_str = json_dumps(a)

    # Escape all the XML/HTML special characters.
    escapes = ['<', '>', '&']
    for c in escapes:
        json_str = json_str.replace(c, r'\u%04x' % ord(c))

    # now it's safe to use mark_safe
    return mark_safe(json_str)