Calculates the MD5 hash of str using the RSA Data Security, Inc. MD5 Message-Digest Algorithm, and returns that hash. MD5 (Message-Digest algorithm 5) is a widely-used cryptographic hash function with a 128-bit hash value. MD5 has been employed in a wide variety of security applications, and is also commonly used to check the integrity of data. The generated hash is also non-reversable. Data canno