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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 v_init_extension(ctx, stmt):
 """find the modulename of the prefix, and set `stmt.keyword`"""

    (prefix, identifier) = stmt.raw_keyword
    (modname, revision) = \
        prefix_to_modulename_and_revision(stmt.i_module, prefix,
                                          stmt.pos, ctx.errors)
    stmt.keyword = (modname, identifier)
    stmt.i_extension_modulename = modname
    stmt.i_extension_revision = revision
    stmt.i_extension = None