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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 resolve_relpath(self, fullname, level):
 """Given an ImportFrom AST node, guess the prefix that should be tacked on to an alias name to produce a canonical name. `fullname` is the name of the module in which the ImportFrom appears. """

        mod = sys.modules.get(fullname, None)
        if hasattr(mod, '__path__'):
            fullname += '.__init__'

        if level == 0 or not fullname:
            return ''

        bits = fullname.split('.')
        if len(bits) <= level:
            # This would be an ImportError in real code.
            return ''

        return '.'.join(bits[:-level]) + '.'