complex([real[, imag]])

Creates a complex number with the value real + imag*j or convert a string or number to a complex number. If the first parameter is a string, it will be interpreted as a complex number and the function must be called without a second parameter. The second parameter can never be a string. Each argument may be any numeric type (including complex). If the second parameter is omitted, it defaults to zero and the function serves as a numeric conversion function like int, long andfloat. If both parameters are omitted, returns 0j.