python - Flask app keeps returning error 500 -

i have been learning how use flask framework using tutorial, code in app.py keeps returning error 500, , can't figure out why (my code identical tutorial).

here's app.py:

from flask import flask, render_template, json, request flask.ext.mysql import mysql werkzeug import generate_password_hash, check_password_hash  mysql = mysql() app = flask(__name__)  # mysql configurations app.config['mysql_database_user'] = 'root' app.config['mysql_database_password'] = 'root' app.config['mysql_database_db'] = 'bucketlist' app.config['mysql_database_host'] = 'localhost' mysql.init_app(app)   @app.route('/') def main():     return render_template('index.html')  @app.route('/showsignup') def showsignup():     return render_template('signup.html')   @app.route('/signup',methods=['post','get']) def signup():     try:         _name = request.form['inputname']         _email = request.form['inputemail']         _password = request.form['inputpassword']          # validate received values         if _name , _email , _password:              # good, let's call mysql              conn = mysql.connect()             cursor = conn.cursor()             _hashed_password = generate_password_hash(_password)             cursor.callproc('sp_createuser',(_name,_email,_hashed_password))             data = cursor.fetchall()              if len(data) 0:                 conn.commit()                 return json.dumps({'message':'user created !'})             else:                 return json.dumps({'error':str(data[0])})         else:             return json.dumps({'html':'<span>enter required fields</span>'})      except exception e:         return json.dumps({'error':str(e)})         return traceback.format_exc()     finally:         cursor.close()          conn.close()  if __name__ == "__main__":     app.run(port=5002) 

it's signup system.

a 500 error means there error in python instead when run try withh app.run(port=5002,debug=true) wont solve problem ... should tell whats going on