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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 get_variable(assignable):
 """ Return modified variable name. "Name(id='a', ctx=Load(), annotation=None)" """

    msg = "Only name and subscript can be assigned."
    assert isinstance(assignable, (ast.Name, ast.Subscript)), msg
    while isinstance(assignable, ast.Subscript) or isattr(assignable):
        if isattr(assignable):
            assignable = assignable.args[0]
        else:
            assignable = assignable.value
    return assignable