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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 _check_for_definition(iface, cls, tag, defines):
 """Check for a valid definition of a value. Args: iface (Iface):
 An Iface specification. cls (type):
 Some type to check for a definition. tag (str):
 The name of the tag attribute used to mark the abstract methods. defines (callable):
 A callable that accepts an attribute and returns True if the attribute is a valid definition. Returns: bool: Whether or not the definition is found. """

    attributes = (
        attr
        for attr in iface.__abstractmethods__
        if hasattr(getattr(iface, attr), tag)
    )
    for attribute in attributes:

        for node in cls.__mro__:

            if hasattr(node, attribute) and defines(getattr(node, attribute)):

                return True

    try:

        attribute
        return False

    except NameError:

        # Pass the test if the loop was never executed. This indicates there
        # were no iface elements defined in the search.
        return True