And, anyway, %hash = {} does not do what himanshu.padmanabhi think it does. To clear a hash in perl, we do:

%hash = ()
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or

undef %hash
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or, if $hash is a hash reference,

%$hash = ()
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or, somewhat similarly but not exactly the same,

$hash = {}
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or, also somewhat similarly but not exactly the same,

undef $hash
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