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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 copy(self):
 """Returns a copy of the context."""

        other = ContextModel(self._context, self.parent())
        other._stale = self._stale
        other._modified = self._modified
        other.request = self.request[:]
        other.packages_path = self.packages_path
        other.implicit_packages = self.implicit_packages
        other.package_filter = self.package_filter
        other.caching = self.caching
        other.default_patch_lock = self.default_patch_lock
        other.patch_locks = copy.deepcopy(self.patch_locks)
        return other